MTS Bad service and customer support

MTS dongle advertises on giving upto 9.8 Mbps.I got only 0.5 Mbps and reported the same to MTS.I have informed to their customer service.MTS responded very late and could not improve the service anyway.The onsite service agents have files with lot of complaints from customers for low speed.

I informed MTS that I will pay the bill as per the speed provided, and I made payment of 50% of the bill amount though I got less than 10% of speed as advertised. MTS disconnected without prior information and later refused to take the dongle back and forcing and sending messages to pay the bill.Why should we pay for bad service?