Account issues

My contract expired end of August 2021 so I had to pay the full contract amount for this month, a lower amount was Abducted from my account for September because I have not renewed or upgraded my contract and only continued to pay for the data package I was on. For the month of September the original contract amount was abducted from my account again and I have been trying to resolve this issue for more than a week, spoke to numerous agents on the phone but no one can assist with the account issue.