Handed over for questionable account

I would like to report on the extremely poor customer service I have received from MTN. In July of 2014 I received a very high internet account from MTN. We had a contract ****le with MTN for our home internet usage. The account was for around R1000. Immediately we questioned the amount. We called into MTN on numerous occasions to inquire about the account but they could not assist in showing us how we had run up such an astronomical bill. We have made numerous attempts to get to the bottom of this but MTN no longer communicates with us. Today I received a call from a Debt Collector stating that MNT handed us over for this account to the amount of over R10000. I can't understand where that amount comes from nor why no one from MTN has ever made any effort to contact me in over 6 months. I am extremely disappointed with MTN, having been a loyal customer for over 10 years. It cannot be that difficult to provide me with a print out of the usage stats & which websites were visited as well as from which location they were accessed. With all the mobile ******** activities, I feel I was within my rights to question this account & get an accurate answer. All we asked for was proof.