MTN FAILURE TO UPDATE DEBIT DATE

I Contacted mtn call centre around the 20th September 2024 to change my debit date from the 2nd to the 15th of which the agent has not done. I contacted mtn today thrice regarding my debit date not being chnaged on the third call when I was eventually transferred to a manager Mandy. Mandy dropped the call without even speaking to me. I want to be reimbursed the rejection fees I am being charged by the bank due to *********** agents