I've had enough with MRP Mobile

Last month I took a contract with MRP Mobile, initially I was told I'm gonna be paying R99.00 a month, when I receive a tablet, it came with a contract stating I'm gonna be paying R129.00 a month, I queried that and they told me they are gonna sort it out(of which I'm hoping they will). So now the problem that I'm experiencing is that, as from Sunday(15 May) I can't access the internet on this tablet, I can't even make calls yet I have enough data, and I'm expected to pay the full amount at the end of the month. I tried calling their customer care line and I'm being told to go directly to the store cause they can't pick up my information, of which it doesn't make any sense to me cause last week they were able to pick up my information. I am seriously fed up by their service.