Settlement?

So firstly, on a monthly basis, 50% of my monthly installment is taken for 'interest'. When I queried this, the response I got was "We take interest and other fees due to us". No way did I sign a contract agreeing to pay 50% interest on a credit. I can assure you of this. Now I decide to cancel my services - so I log into my online profile, download a settlement letter - and merely contact African Bank for an email address to which I can send proof of payment, and request for account closure. They refuse to help me. They first need to phone me to confirm my personal details before being able to provide a service. Im not asking you for anything other than an email address to cancel my services with you - this should be publicly available - but ofcourse isn't cos you make it as difficult as possible for you clients to leave. The longer you can keep information from me the more interest you get to add to that settlement of mine right?

I will now go waste my time in the branch tomorrow and get this resolved, but I will never, ever, be an African Bank client again. What a complete and utter ******* this was.