Cancel late payment arrangement

I talked to a service agent and agreed to pay my bill today using my att app and saved debit card ending in **. I made the payment in full but forgot that I had a late payment arrangement set up for April 14. It says it cannot be canceled and I do not want to pay it twice.

[Edited for privacy-This is a public forum. 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.]