Hello @Chadg78,
I apologize if the above link was unable to resolve your myAT&T app concern. I definitely want to help get this taken care of for you.
Is your balance displaying correctly online through your browser? This will help narrow down what is causing the issue. You will also want to force-close the application and re-open it to make sure it pulls the most recent information from your account. You can complete this by double tapping the home button on your iPhone. This will bring up the open applications in your background. Swipe up on an application in order to force-close them.
I hope to hear from you soon!
Jessica, AT&T Community Specialist