To resolve the issue with the Meijer app not opening and your inability to sign in, follow these step-by-step instructions:

1. Restart Your Device: Sometimes a simple restart can fix app glitches. Turn off your device completely, wait for a few seconds, then turn it back on.

2. Check App Status: Verify if the Meijer app is experiencing outages. You can visit a website like "Is It Down Right Now" to check for any known issues with the app's servers - learn more.

3. Update the App: Ensure that your Meijer app is updated to the latest version. Go to the App Store, search for Meijer, and if you see an "Update" option, select it.

4. Clear Cache: Clear the app cache to remove any stored data that might be causing issues. For iOS, go to Settings > General > iPhone Storage, find the Meijer app, and choose "Offload App" or "Delete App" to clear data - learn more.

5. Reinstall the App: If the problem persists after clearing the cache, delete the Meijer app entirely from your device and then reinstall it from the App Store. This can resolve any corruption issues - learn more.

6. Reset Password: If you still cannot sign in, it's worth trying to reset your password. Visit the Meijer login page on a computer, click on "Forgot Password," and follow the prompts. Sometimes password issues can prevent login - learn more.

7. Check Network Connection: Ensure that your device is connected to a stable internet connection. Poor connectivity can prevent apps from logging in or functioning properly.

8. Contact Support: If none of the above solutions work, reach out to Meijer customer support for further assistance. You can find contact information on their website or use community forums to see if others are experiencing similar issues - learn more.

Following these steps should help you address the issues with the Meijer app.