Monthly EFT not being deducted from my account

3 months ago I entered into a internet contract with Telkom. Everything was fine till I was disconnected for not paying my account. On investigation with Telkoms call center I was 3 months in arrears, and that my debit order was rejected by the bank (funds always being available). Telkom confirmed that all my details are correct on their system. I was told by Telkom to speak to my bank. I spoke to my bank and they said its Telkoms problem speak to them. I went to a Telkom office, but they don't deal with such matters I have to go through the call center. This is madness where is the customer service, you just get pushed from pillar to post.