Bad service,no the worst

I am so upset ,I am banking with capitec dit 13 years,I have sold Hyundai i10 to client and her driver bump the car now she wants her money back.the send false ***** claim to capitec and capitec froze all my accounts and all my suppliers account. The promise to get back to me after all documents have been given to them on the 15 Decmeber.

I have clean 13y record with capitec and they cant even call me or let me know about the complaint and no feedback as well spend 300 on airtime and still no where .

How do you keep your client and their money safe .