Extremely bad service

Appalling!!!! Besides the ridiculously bad service and almost no signal...I am having the most difficult time in having my cancelation date corrected. I called, emailed and went online and cxd my rain sim mid Feb. I was assured that the end of Feb would be my last cover and from March I won't have it active anymore...this did not happen. I called the call centre yesterday and spoke to an arrogant smart-ass whose was extremely unhelpful and rude. I then got put to a supervisor who assured me that I would receive my invoice by yday afternoon and that my cancelation would be sorted for end Feb...NOTHING!!!!