I had the notice from t-mobile however every time i went to change my autopay settings from a CC i was presented a page saying "not available at this time". I t

I had the notice from t-mobile however every time i went to change my autopay settings from a CC i was presented a page saying "not available at this time". I then get to a screen where i updated debit and bank and marked it as "default" but come to find i didnt find the hidden box to migrate over to autopay. I still dont know where that it. i got stuck with the $5 hit this month.