Poor service

I'm extremely frustrated and shocked with the level of service in dealing with my billing query on my loan account at standard bank. I've been paying my account and it seems the more I make my monthly payments the more I owe. I went to the branch numerous times Sanridge (Midrand), Jabulani Mall (Soweto) and Forest Hill (Centurion) just to name a few. The response I received has not been consistent from one branch to the other and recently I was informed that there seems to be a mistake in my billing. Interest is changed twice on my account and a query was logged (ref number ***) due on 14/05/2015. I haven't received any communication and each time I try and call the *** I get no response. This has been going on for far too long and I need it resolved.