Very bad service and no systems

I have a data contract with them with a billing date that I honour. I payed on my billing date and my sim is locked, this is the worst service provider and the sad part is that it is not the 1st time they are doing this to me. I went to MTN Store many times💔💔💔😭their call centre agents even disrespect the shop attendants and they are unable to assist. This morning I also tried their call centre and eventually managed to go through to their agent and while we were still talking she got cut off and she never bothered to call me back. I have given up on you and your **** service. You do not respect your customers at all.