Bad service from mtn

K have a problem with the account i have with mtn og which they have failed tl resolve several times, someone called mtn with a private number and requested data and minutes but that was not me i told them to do a voice recognition og me and the caller but they did not when these things were loaded to enquire about them the agent said it was a gift from MTN that i won but nkw they saying i must pay for it. Ref for this case ***. So disappointed