Settlement of account

I had a contract with Wesbank for vehicle finance when I was involved in an accident in April and my car was declared a write-off. Firstly, the very first contact I had with Wesbank after was via a sms in which they threatened to blacklist me if I did not settle my account immediately - completely uncalled for as I had not missed one payment since the inception of the contract. No way to treat a good client. Secondly, my insurance company requested a settlement letter and settled the balance then a little while after that I got a message from Wesbank saying my debit order was being reinstated and then an amount was deducted from my account. I phoned several times to query this, the first three times I sat on hold for more 10 minutes or more. Then eventually I got in contact with someone who said there was a problem and she needed to do some calculations then she would call me back - I'm still waiting. I have attempted to call them again but have again had to hold for more than 10 minutes at a time. Terrible, terrible service! I will need to purchase a new car soon and I am reluctant to use Wesbank to finance it.