Absa debit

I have a vehicle finance with Absa, since from 2023 till today they have been debiting lot of money for my car service but the car is only serviced once , every time I call VW for my car service they tell me that Absa didn't authorized the car service, then I've called absa to cancel the debit because it doesn't help me instead they just keeping me off, then they said they will cancel it till today I have been paying for a service that I donr get. So I need refund and the debit order must stop.