Overcharging

So after 7 years of being with MTN and always having a top up account, all of a sudden, the soft lock on my account was no longer there and i have been receiving bills of R4000?!?!<br> <br> When I inquired how this happened, they told me that I didn't complain within 3 months so therefore they presumed i was enjoying the contract?!?! <br> <br> I can't even make a call from within my own home & when MTN themselves try and contact the relevant department to correct my signal issues...they are on strike so there is nothing they can do.... but they will happily bill me up to nearly R4000 when I have always had a Top up account with a limit on it which i was told would continue but that I just upped the amount of minutes & data I would need in a month. My limit was supposed to be set at R720 as it always has been.<br> <br> They told me there is nothing they can do & that it is my issue for not <br> <br> CELL C ... please buy me out of this contract.