Telkom contract porting of telephone numbers

I accepted a Telkom contract offered to me by Mondo. Received sim cards, but since middle of December, no one can assist with the porting of existing telephone numbers. Followed up various times without response or feedback. When it is time for the debit order to go off, I am sure that they will not accept excuses for not paying?? However why can I not get assistance in such a easy request? CAN I PLEASE GET SOME SERVICE? You will request payment at the end of the month for a service that I cannot make use of.