MTN Bad Service

I believe Mtn South Africa is has grown too big that they are no longer taking care of their clients as is been 6 Months I’ve been complaining about data and minutes they added on my package however they only keep demanding payment from me even though I’ve been calling for that package that it’s contract has expired and they don’t even respond to my emails of which I’ve sent proof that I’ve been calling and sending smses of demand from me to their client service agent through emails to Emihle Landu ,retentions and ***.