Unfair Payment demand by Netstar

The company took my money in a wrong manner, I bought a car in July 2021 and in March they deducted R450 in my account without my knowledge, I reversed and send them email to stop deducting money explaining that I according to my knowledge. I even phone them and was told I have their tracker and they said my be deal was done with my dealership, I requested that they send documents that were signed by myself and installation certificate and also cancel whatever deal or dream because I had my tracker and I am happy paying SecureDrive every month.

They continue phoning sending me messages that I am owing them R450 and they were going to blacklist me on the 25th I paid R450 in the account that was provided with the cell no and I phoned also send email to a lady called Kgomotso Moumakwa I also asked her about my balance according to them and she said it was R2090 I phone and her my previous communication with Netstar she then changed and said the balance was now R227.00 of which I am still not happy about it