Mtn SA is a ****

Mtn is a ****, I canceled 3g that I bought from them cause was not using it, they delayed the response then came back to me by saying must pay the money i owe them i asked for somwthing im not using instead they handed account to nudebt I settled the account up to date I have not received paid up letter. I sent them numerous emails mtn does not reply .nudebt keep on saying send proof of payment poff it was sent 100 times when you call nudebt they say : mtn should issue paid up letter to them and can take 3months heeeeeheee life will humble you