Bad connection, worse service

I bought what I thought to be a 5G lte router 6 months ago and I've never received any 5G coverage and the little connection I did get was bad and inconsistent. In December I started calling their customer care line and after sales departments for assistance. I was transferred to back-end support who took my address and confirmed that their coverage doesn't reach my area and went as far as saying I shouldn't have been sold the service because of this. Fast forward I reported it and they promised to come take their router and start refund proceedings which hasn't happened, after their collection I was told to wait for confirmation that they have received the router and will start refund talks I've yet to receive any of those comms.

I went back to the store where I bought it, I was given a reference number, and a collection barcode from the courier who collected my router. I've called they're after sales department, passed on to their customer service line then told to wait to be contacted. This has been going on for 3 months now

I've now started getting emails that I owe them for a service I'm no longer receiving.

Vodacom shop from Durban, Bluff towers hasn't come to my aid as a customer to resolve this in store as the ones who sold me the service.