Ridiculous service

For the past 5 months zelna from finance kilokor motors has been harrasing me with making a payment amount of R1633 which she says was from all the bounced debit orders from all the years and threatening to switch off my car. My car installments are up to date. In Aug my car was in for a service they broke my rear mirror and promised to call me to fix it, to date am driving without a rear mirror. I have reported several times that ever since I collected my car 4 years ago the central locking in car is not working only got a reply last week from Jeremy to bring in my car. I get emails smses and whatsapp messages to pay money that came out all of a sudden. I phoned in several times when my car couldn't start in the mornings was told to phone the workshop where no one answered and had to figure out how to fix my car.