MTN is appauling

MTN has owed me R400 since october 2020. I have spoken to atleast 10 different people and each person has promised my refund within 21 days. I was a paying customer for 3 years and paid up my contract. These companies are quick to take take take your money.. now they ***** too! Disgusting behaviour and seriously bad management.. I will never use mtn again and i will make sure everyone i know moves over to a more reliable and honest provider