Automatic payment processing

I have my account set up for automatic withdrawal for both my convenience and yours. What is not convenient is receiving a text telling me AT&T is randomly changing the billing date, then proceeding to skip a month's payment, followed by taking two months out at once then charging a late fee. If there was a problem debiting my account, a heads up so I could call my bank and fix the problem would have been nice. Or at the very least, an explanation as to why this was occuring. I work long hours, squeezing in a phone call to customer service which often takes hours to sort out isn't very feasible for me, so I greatly appreciate the online services when functioning properly.

What I'd like to know is how to avoid this happening again the next bill cycle. Thank you in advance!