Lack of service

I have taken out a contract with Mondo, Telkoms online store. After given them my banking details and them setting up a debit order. I got a call from their attorneys for non payment. I have been phoning non stop to get this sorted, I contacted Telkom, Mondo and Hammond Pall their attorneys. NO ONE gets back to you or seems really interested to help you. After I investigated myself l, I found that Mondo and Telkom has two different bank account numbers for me. Either Mondo never updated telkom AFTER setting up a debit order on my account or Telkom never updated their system after receiving the information from Mondo. I have been running around to get this sorted, which is not my mistake but incompetence from Telkom and Mondo. To date no one has contacted me after leaving numerous messages with all 3 parties involved. This is Truly the worst customer service.