MTN Month to Month contract

I am disappointed with the service I’m getting with MTN , I am on month to month contract with them where I have been requesting for bank details to be updated and a change of the date it took almost a month to be attended to and it still was not done correctly I opted to pay the account myself only to be told by Palesa Phoku that my service will only be re-instated on the 1st of February due to no payment in December I don’t understand because this is a month to month contract and states on their statement that my account will not be affected if no payment is received