Disgusting 🤮 customer service

What a disgusting customer service this MTN momo offers. I recently bought a voucher through this momo app and I didn't get a voucher number. When I do a follow up I was given used voucher number instead of the requested one. I did the second follow up they now rejected my query without any accompanying feedback or reason, the level of incompetence in this MTN call centres is very scary, their agents are just useless, when you ask questions they always don't know very useless and ***********..