Double debit over festive period. Unable to get assistance from MTN

I am a recent new client to MTN and i am definitely not pleased with the level of service experienced so far. The latest pathetic service by MTN is that they double debited me for current contracts. I called their head office and conveniently closed until the 3rd January. The call centre number 083 135 is just useless as there is no option to speak to consultant. THERE IS NO ASSISTANCE FROM MTN!!!!!!!.