Problems with 5g mobile network

I wanted to get internet that requires a 5G network and a SIM card. However, my ISP supposedly checked it on a computer and told me that I can't get that network because my area is not covered by a 5G network. I claim that it is and I'm sending some photos of an internet speed test, a router that works over a 5G network.... my house is 700 meters as the crow flies from a repeater and the signal for both 4G and 5G is always 5 bars. What should I do, how can I convince them that I want it, i.e. I've already ordered a 5G dual SIM card wifi router with 4 gigabit ports and a 2.5 GB WAN port, and 3 pieces of 1.5 m cat 6 cables. For networking over wifi, it's not so lucky. In games, it fluctuates too much from 170 to 50 mbit/sec downloads, but over cable it's a different story. Through the WAN cable, the speed is excellent (between 200 and 220 mbit for download and 70-80 mbit/upload. Latency is much lower than via wifi. Although I bought a TV with Allm, I think that's the name of the option where it automatically reduces latency. For 550 euros, it's a best buy gaming TV. Only smart tv, laptop and ps5 will be connected to that new router.