Poor communication

I took out a sim contract with Vodacom in last year july. I then decided I do not want the contract anymore and cancelled it with in the 14 day cool off period. Thinking all is well then a few months later I got an email saying I was handed over and owe them money, but Vodacom never contacted me. I have a reference number given by the Vodacom call centre. I have sent all this information to the lawyers that contacted me and it's as if they just don't care and its showing negatively on my credit record. Will never work with Vodacom ever again. Biggest ********s in the country