Mtn consultants don't have customer service!!

I signed up for a free to use router,used the router for almost a year. Throughout my usage I constantly had to call into the mtn call centre to query the bad signal this went on every second week if not every month. Finally decided I'd had enough and called in to enquire how to proceed with cancelation. I WAS TOLD TO GO INTO THE STORE TO RETURN THE ROUTER!...RIGHT.. Went into the store the consultant present told me that she'd book the router for return and I even had to come back into the store because I didn't have a invoice of the agreement amd I did return with the needed documentation. This all was before the end of July... Aug the 2nd I get billed ?? Spoke to mtn via email which they were of NO USE! Okay then when I called in I'm now told story about the store doesn't cancel online purchased routers?? First time I'm hearing of this...anyway and that the consultant couldn't get ahold of me but yet had me on WhatsApp to send me the IRMS number so I honestly don't know who they trying to make stupid but I'm SICK of mtn service as it stems from the EMPLOYEES ...They show that they only at work for their salaries and NOT to serve people as a whole. Now I'm told I have to go back into that exact store to fetch the router and go to head office and discredit my bill. Mtn has to understand that they as people Employees they make mtn what it is ...