Very bad service

I posted some time ago about vodacom and a credit of about R1000 which i was incorrectly charged and was credited to my vodacom "account" and was told any future debit orders would be deducted from this balance but only about two debit orders where taken from this balance and then I was being debited as usual again and nobody can help me with this issue .I'm seriously thinking of moving over to M.T.N