Closed account handed over to the attorney

<p>Between 2010 and 2015 I have been using an company MTN number which was under a business account, upon my resignation in 2015 November. The account was changed to my name as I wanted to continue using the number, immediately after changing the account name I have requested MTN to change it from contract to prepaid as I was not willing to continue with the contract. I was notified that the account has been closed and the plan has been changed to prepaid as requested. Earlier this year I have been contacted by hammond pole attorney to advise that my account has been handed over to them. At first I though maybe I was a victim of *****, after contacting MTN i was told that indeed the account has been handed over but there are no further details wrt the account. I would like to know why the account was handed over as I have never received any communication from MTN before the account was handed over. I have been trying to contact MTN but I can't get any explanation. I have never failed to pay any account/debts before.</p>