Terrible service from MTN

I upgraded my package without a device in March 2018, since then I have been billed for a device. I contacted the MTN Call center on the 8th, 9th, 11th, 14th, 18th, 29th of May and the 1st and 4th June 2018, I have been advised that the problem has been escalated and then resolved on each occasion however to date I have received no solution. I am frustrated and appalled at MTN customer consultants I have dealt with over 8 different consultants and none have been able to communicate in a professional and helpful manner, I found that they are abrupt and *********** and cannot comprehend simple queries.