MTN hands over paid up client, to attorneys be aware

MTN Not even worth the one star!! I cancelled my contract with MTN in Jan2020 and paid the cancellation fee on 8 Feb 2020, i received a email from MTN retentions department that my contract has been converted to a prepaid contract... I left it there, but low and behold in April i received a email from SSDA attorneys, stating that my account with MTN is in arrears!! I send SSDA the proof of payment etc. but I keep on getting phone calls from SSDA(more about this later) now I tried to get hold of MTN but it is impossible to contact Customer service or retentions or anyone, it seems their call centre is setup to keep customers away from the company... very bad service MTN!!!