All accounts suspended after payment

MTN took over all Nashua Mobile contracts. What a disaster!!! I renewed my contract with MTN. The sales person told me that all 3 contracts will only be R200 per month higher (in total). It is R1000 per month higher and they cannot tell me why!!! To make it even worse, I pay by debit order each month on the 2nd. Since I joined MTN, suspended my account on the 23rd after the necessary amounts were paid on the 2nd!!!! Call centre does not answer. I called head office. Tried 7 times. Phone rang for 15min and automatically stopped. The branch is telling me that MTN feels that I cannot afford my account????? I have never in my life missed a payment!!!!! I have free sms, 109 minutes and 1Gb data left, but cannot use it as they feel aI might not pay them. This is the worst service I have received in my life.