No Stock, Staff don't answer phones and no one knows when the stock will arrive!!!!!!

My contract has come up for renewal and I have been trying to contact MTN The Glen, MTN Mall of the South and MTN Sandton and the shocking thing is that NOBODY answers the phone!!!! EVER!!!!!! I've been trying since last week Wednesday. I then went to MTN Mall of the south and MTN The glen as I want to Upgrade to the Iphone 11 Pro Max and guess what? There isn't a single MTN branch which has stock and none of the staff at MTN can tell me when the stock they have ordered will arrive? Really? So do I as an MTN customer wait indefinitely for a phone call from someone which will more than likely not happen or do I take my contract elsewhere to another service provider who answers their phones and cares enough to give me an explanation that makes sense?