Poor service from cell c

I've been trying to cancel my contract for 4 months now. I pay them the money send the proof of payment twice every month and they keep on disconecting my line. The last time the lady i spoke to said that it has been allocated, that was last month now my line is disconnected again. I even send last month and the previous months proof of payments. This is now 3 days later and no contact. There are no cell c shops open in Bloemfontein that i even can go to. I've been a customer since 2013 and now all of a sudden I get poor service. Please can someone help me