MTN bad service. Fixed LTE issue

I have been with MTN for over 10 years and just in 1 month I am wanting to change by cellphone provider. Beginning of this month I signed for a new contract... MTN my home fixed LTE. I am having an issue with my simcard which has been barred (barring). For almost 2 weeks I have called the customer service and even taken this to the MTN store and until now nothing has been sorted. I even want to cancel my device as I have only had it for 3 weeks and no one still replies. If MTN continues to have bad services, they will lose alot more customers. I am one very unhappy customer.