Auto-pay MIX UP

Hello, my husband and I signed up both of our two gophone accounts for auto pay (the $25 a month plan) last month... We both received an atuomated text this month, confirming the auto payment, and then a following automated text a few days later telling us that the service was not renewed because the balance was too low. I just visted my account online (since both of our phones are disconnected now) and it shows a balance pf $24.75 on the accounts, even though my bank statement clearly shows a $25 dollar charge to AT&T. Why wasn't the service renewed? We need our cell-phones NOW. We have no land-line.

Thank you for your time and support