Agent With Stinking Attitude

I phoned MBD on the 26th of February 2016 to ask that my cellphone number be removed from their records because I don't owe any of their clients. A girl named Clarissa answered and bluntly told me to ignore the incessant SMSes I've been receiving and then hung up before I could answer her. I phoned again and spoke to a guy named Meshack who guaranteed me that my number will be removed but that turned out to be a lie because today I received another threatening SMS from MBD saying that I must pay my Woolworths account. I have never had a Woolworths account in my entire life!!! This has been going on for over a year and I have complained several times but nothing seems to be happening to rectify this situation. I have both of the aforementioned call recordings as proof.