Pathetic service!!!!

I have 2 WiFi router contracts with cell c, I have had to do 2 sim swaps last month because one of my SIM cards keeps losing signal, the first time I was told that my SIM card is damaged and the second time too, how? When I didn’t even remove the second SIM card from the time I had inserted it... it worked quite fine and after 2 weeks this **** is happening again, I call in a couple of times with each incident, and I get told that I have to be transferred to another department, every time! Oh and then the call conveniently cuts, every time!!!!! I really don’t think it’s fair for me to pay for a 3rd sim swap over 2 months, there is nothing wrong with the router I’m using as well because the SIM card with the least amount of data seems to be working perfectly, and this is the case every time!!! And also why the **** am i paying for something I can’t use?