AT&T THANKS app login fail

I have tried numerous times to login to the AT&T THANKS app but it always comes back with "Uh oh. An error has occurred. Please check back later." I tried at different times. I tried on wifi or on the phone's data. I tried uninstalling and reinstalling the app. I reset my phone. None of this has worked. 

I saw that someone posted somewhere to try logging in using my phone number instead of my user ID. I tried that and that doesn't work either. I was on with AT&T customer service with 4 different people over 2 hours with no resolution. They finally told me to email the developers and gave me the emal [edited for privacy-please do not post personal or unique information such as but not limited to full names, employee ID numbers, email addresses, phone numbers, account numbers, etc.] to contact. I emailed them and never got a response. 

This is ridiculous! It shouldn't be that hard to fix this issue. I can login online and on the myAT&T app with no problems. It's just AT&T THANKS that has this issue. Any help?