DEBITED MY ACCOUNT WHEN I SUPPOSED TO BE CREDITED

So I decided to take out car insurance with discovery...over the phone the consultant that assisted me was very quick to take down my banking details and set the debit date...after a few months I sold my vehicle and notified discovery so the tracker can be taken out...this was in December...1-I was debited for a month despite cancelling my insurance. 2-After numerous phone calls that I made to discovery and the various call centre staff that I have spoken to, I was told that as soon as the tracker is removed , they will credit me with the funds that THEY debited from MY account.3-The tracker was finally removed from the vehicle BUT NOW INSTEAD OF BEING CREDITED , I HAVE BEING DEBITED WITH AN AMOUNT OF R1100 WHICH IS MORE THAN WHAT MY MONTHLY PREMIUM USED TO BE. The sad part is that despite all the queries that I have made, Discovery has not even called me once out of courtesy to update me . I have wasted my time and many many phone calls to them only to have to phone them yet again to try and get my payment sorted out. Its so dissapointing that the call centre staff that I spoke to on the numerous occasions all assured me that its in the \process "of being sorted out. """