To resolve the issue of the 7-Eleven app crashing upon login and the website not generating a code, follow these detailed steps:

1. Check Internet Connection:
- Ensure you have a stable internet connection, as connectivity issues can cause app malfunctions. You may try switching between Wi-Fi and mobile data to see if that resolves the problem.

2. Restart Your Device:
- Perform a simple restart of your device. This can refresh system resources and clear temporary glitches that might be causing the app to crash.

3. Clear App Data:
- In addition to clearing the cache, consider clearing app data:
- Go to Settings > Apps > 7-Eleven App.
- Tap on Storage and then select Clear Data. This will reset the app and may fix login issues.

4. Update the App:
- Ensure you have the latest version of the 7-Eleven app:
- Go to the App Store (iOS) or Google Play Store (Android) and check for updates. Install any available updates for the app.

5. Check for System Updates:
- Make sure your device’s operating system is up to date:
- Go to Settings > About Phone > Software Update and download any available updates.

6. Date and Time Settings:
- Verify that your date and time settings are correct and set to automatic:
- Go to Settings > Date & Time and enable Automatic date & time.

7. Reinstall the App:
- Since you have already uninstalled and installed the app, ensure that you remove it completely:
- Uninstall the app, restart your device, and then download it again from the App Store or Google Play Store.

8. Contact Customer Support:
- If the app continues to crash upon login or the website does not generate a code, contact 7-Eleven customer support for assistance. You may need to report the issue directly if it is related to server problems or account-related issues.

9. Try Using a Different Device or Browser:
- If possible, attempt to log into the app or website from another device or using a different browser to see if the issue persists. This can help determine if the problem is device-specific.

These steps should help resolve the crashes and the login issues with the 7-Eleven app. If you need further assistance, you can refer to user experiences and solutions available on community platforms such as Reddit - learn more or watch video guides on troubleshooting the app - learn more.