Hello @samsherman,
Thank you for reaching out to the Community Forums! Not being able to access your online account to make a payment is concerning. Let’s get your access back ASAP!
Have you tried using a different browser to access your myATT account? If not, please try using a different browser. Another thing you can do is clear the cache and cookies of the browser; close and then reopen it before trying to log into your myATT account.
If it still is not accepting your User ID/Password combination, you would need to click on "Forgot ID/Password" and follow the prompts to reset the password.
For the myATT app; one thing you can do is go into Settings > Apps> Application Manager (if your device has this option) > All> myATT app> Clear cache> Clear Data> Power cycle device and then sign on again.
If you are still not able to log in using the myATT app, then uninstall the app from the phone completely and re-download it. Once it has finished installing, sign in once more.
Hopefully these steps will work. Have a fabulous holiday season!
Katherine, AT&T Community Specialist