STILL NO ACTION FROM MTN

Lodged a complaint on HelloPeter on 5 April. MTN was quick to call back, but as usual absolutely nothing has happened. Everytime I speak to a person, I get their name. Everytime I try to contact them again it is like they do not exist. So in spite of the umpteenth promise to stop billing me for a device that I transferred/canceled/converted more than two months ago, I am still getting billed for it with no indication when this is going to stop! Your service SUCKS MTN, and this from a customer who has been with you for twenty years. Your Retentions department should be renamed, because they do anything but put effort into retaining existing customers. I guess your Billing department should equally be disbanded, because they're incapable to following simple instructions to STOP BILLING me and to refund me money erroneously deducted !!!!