If your Instacart Android app is not completing payment after an update, you can follow these steps to troubleshoot and possibly resolve the issue:

1. Restart the App: Close the Instacart app completely and reopen it. This can help refresh the app and may resolve temporary issues.

2. Check Payment Method: Ensure that your payment method is correctly entered and still valid. You can do this by navigating to your account settings within the app and reviewing your payment methods. If necessary, re-enter your card details to avoid errors - learn more.

3. Update Payment Information: If you recently received a new card or changed your bank account, update your payment information in the app. Go to your account settings, locate the payment section, and update your card information. Make sure to save the changes - learn more.

4. Check for App Updates: Sometimes, subsequent updates may fix bugs introduced in previous versions. Visit the Google Play Store, search for the Instacart app, and ensure it is updated to the latest version.

5. Clear App Cache: Clearing the app cache can resolve performance issues. Go to your device's Settings > Apps > Instacart > Storage > Clear Cache. Restart the app afterward.

6. Reinstall the App: If the problem persists, uninstall the Instacart app and then reinstall it from the Google Play Store. This process can eliminate any corrupt files causing the issue.

7. Check Network Connection: Ensure you have a stable internet connection. If you are on a Wi-Fi connection, try disconnecting and reconnecting, or switch to mobile data, if available.

8. Contact Support: If none of the above steps work, reach out to Instacart's support team. They can offer assistance tailored to your specific problem - learn more.

9. Monitor for Bugs: Occasionally, app updates may introduce bugs. Check platforms like Reddit for any ongoing discussions regarding similar issues experienced by other users - learn more.

Performing these steps should help you resolve payment issues within the Instacart Android app following an update.