Terrible service

I have 2 sims (one is an unlimited 4G at R479 per month and the other is a 5G for home at R699 per month). My 4G service has been working reasonably well, however the 5G service has been terrible. I am now sitting with no service on the 5G router as it says that the registration has failed. There has been no joy from Rain support whatsoever. If someone could contact me urgently, that would be great.