Poor service and harrassing clients for payments they said not due

When I bought my card in 2020, the garage got me a 3 year contrack with Cartrack. Never had any issues. Beginning August I got a whatsapp that my account in in arrears. I called them and said that no one contacted me to say the contract expired and no one ever took my banking details. That call was on 10/08/2023. I asked them that I want to downgrade the package for the R99pm one. I spoke to a lady and she advised me that I need to pay R350 downgrade fee and I was fine with that. As the call continued, she said that the system says the downgrade is free and I am not going to pay the R350. I asked her about 3 times are you sure I am not going to pay the R350 and she said again no i am not going to pay that amount. Few days later I got a msg again that the account is in arrears and I made payment online. 2 days later they deducted in from my bank account also. I called them and they told me there is an arrears of R350. I told the consultant what happened and the lady said I am not going to pay the R350. They said they will get the call and come back to me. 20 min later a very rude guy called me and said I owe them the R350 and should pay it before COB that day. I called in again and another lady said she will get the call from 10/08/2023 and listen to it. Today is 08/09/2023 and no one came back to me. I did however get a call now to say my account is arrears for an amount above R400. So I want this sorted. I WILL NOT pay the R350 as the lady told me the system said its for FREE.