# Use Case 2.6 Change remote PIN

## Overview

| Aspect                       | Description                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| **Summary**                  | The user changes their PIN by first entering the current one, then choosing and confirming a new PIN that meets policy requirements.                                                                                                                                                                                                                                                                                                                                                                                     |
| **Goal**                     | Changing the remote PIN.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| **Preconditions**            | <ul><li>User completed [UC3.1 Obtain PID from provider](UC3.1_ObtainPidFromProvider.md)</li><li>User completed [UC1.2 Open the app](UC1.2_OpenTheApp.md)</li></ul>                                                                                                                                                                                                                                                                                                                                                       |
| **Postconditions**           | <ul><li>User can use the new PIN in the Wallet.</li><li>User can no longer use the old PIN in the Wallet.</li></ul>                                                                                                                                                                                                                                                                                                                                                                                                      |
| **Triggered by**             | <ul><li>User selects 'Change pin' in [UC9.1 Show app menu](UC9.1_ShowAppMenu.md).</li></ul>                                                                                                                                                                                                                                                                                                                                                                                                                              |
| **Additional Documentation** | <ul><li>[PIN validation](../../architecture/use-cases/pin-validation)</li></ul>                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| **Possible errors**          | <ul><li>No internet</li><li>Server unreachable</li></ul>                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| **Logical Test Cases**       | <ul><li>[LTC56 PIN Change Happy flow](../logical-test-cases.md#ltc76)</li><li>[LTC61 PIN entries do not match, try again](../logical-test-cases.md#ltc77)</li><li>[LTC62 PIN entries do not match, choose new PIN](../logical-test-cases.md#ltc76)</li><li>[LTC63 PIN entry does not conform to policy](../logical-test-cases.md#ltc77)</li><li>[LTC64 PIN change fails, could not reach server](../logical-test-cases.md#ltc77)</li><li>[LTC65 PIN change fails, no internet](../logical-test-cases.md#ltc57)</li></ul> |

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## Flow

| #       | Description                                                                                                                                           | Next                                                                    |
| ------- | ----------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------- |
| **1**   | **PRIMARY SCENARIO**                                                                                                                                  |                                                                         |
| **1.1** | **System executes partial flow [PF2.4 Confirm a protected action](../partial-flows/PF2.4_ConfirmProtectedAction.md)**<ul><li>Not cancelable</li></ul>                |                                                                         |
| 1.1a    | Result: Confirm                                                                                                                                       | 1.2                                                                     |
| 1.1b    | Result: Back                                                                                                                                          | Back                                                                    |
| **1.2** | **Displays screen 'Choose new PIN'**<ul><li>Message: Choose a new 6-digit PIN</li><li>Input: 6 digits (0-9) PIN field</li><li>Actions: Back</li></ul> |                                                                         |
| 1.2a    | User enters PIN                                                                                                                                       | 1.3                                                                     |
| 1.2b    | User selects Back                                                                                                                                     | Back                                                                    |
| 1.2c    | Error: No internet                                                                                                                                    | Error flow: No internet                                                 |
| 1.2d    | Error: Server unreachable                                                                                                                             | Error flow: Server unreachable                                          |
| **1.3** | **System validates entered PIN against PIN policy**<ul><li>Duration: 0.0 - 0.1 seconds</li></ul>                                                      |                                                                         |
| 1.3a    | Case: PIN matches PIN policy                                                                                                                          | 1.4                                                                     |
| 1.3b    | Case: PIN does not match PIN policy                                                                                                                   | 2                                                                       |
| **1.4** | **System displays screen 'Repeat PIN'**<ul><li>Message: Repeat your new PIN</li><li>Input: 6 digits (0-9) PIN field</li><li>Actions: Back</li></ul>   |                                                                         |
| 1.4a    | User enters PIN                                                                                                                                       | 1.5                                                                     |
| 1.4b    | User selects Back                                                                                                                                     | Back                                                                    |
| **1.5** | **System validates PINs match**<ul><li>Duration: 0.0 - 0.1 seconds</li></ul>                                                                          |                                                                         |
| 1.5a    | Case: PINs match                                                                                                                                      | 1.6                                                                     |
| 1.5b    | Case: PINs do not match first time                                                                                                                    | 3                                                                       |
| 1.5c    | Case: PINs do not match second time                                                                                                                   | 4                                                                       |
| 1.5d    | Error: No internet                                                                                                                                    | Error flow: No internet                                                 |
| 1.5e    | Error: Server unreachable                                                                                                                             | Error flow: Server unreachable                                          |
| **1.6** | **System displays screen 'PIN change success'**<ul><li>Message: Success!</li><li>Actions: Dashboard, Settings</li></ul>                               |                                                                         |
| 1.6a    | User selects Dashboard                                                                                                                                | Go to: [UC7.1 Show all available cards](UC7.1_ShowAllAvailableCards.md) |
| 1.6b    | User selects Settings                                                                                                                                 | End                                                                     |
| **2**   | **WHEN PIN DOES NOT SATISFY POLICY (TOO SIMPLE)**                                                                                                     |                                                                         |
| **2.1** | **System displays PIN too simple message**<ul><li>Actions: OK</li></ul>                                                                               |                                                                         |
| 2.1a    | User selects OK                                                                                                                                       | 1.2                                                                     |
| **3**   | **WHEN PINs ARE NOT EQUAL (FIRST TIME)**                                                                                                              |                                                                         |
| **3.1** | **System displays PIN is different message**<ul><li>Actions: Try Again</li></ul>                                                                      |                                                                         |
| 3.1a    | User selects Try again                                                                                                                                | 1.4                                                                     |
| **4**   | **WHEN PINs ARE NOT EQUAL (SECOND TIME)**                                                                                                             |                                                                         |
| **4.1** | **System displays PIN is different message**<ul><li>Actions: Choose New Pin</li></ul>                                                                 |                                                                         |
| 4.1a    | User selects Choose New Pin                                                                                                                           | 1.2                                                                     |