Unsatisfied CellC client

I signed on with Cell C and took a wireless router ZTE,lately ive had very weak reception,takes longer to send an email than to post it at the post office. I reported that the battery has swollen to 3 times it size. Today I phoned again to complain about the above,but I just got transferred from one to another department. Eventually I was transferred to repairs dept. only to be cut off!! I only have 3months left on my contract,seems like Cell C has collected enough money from me in the last 21 months that they don't have to bother to assist me any more. Ive been a dedicated payer for 21 months now but now I must continue paying for a faulty device?Why? Cell C did not even return a call once the line was dropped. Now I ask...Is this the type of service delivery that one has to pay for?