How to get stable internet

I just bought the 200 Mbps (not megabyte but megabit) for 6 months for airerl xtreme fibre

And after few tests, the wireless speed is not at all suitable for multiplayer games like valorant, by checking the internet speed it gives 180+ download and upload speeds but the ping test shows 55 or 80 for 3 seconds then 180+ ping

I checked the ethernet speed and it was good, stable 200 mbps with 50-55 ping

We had this problem previously so the company guys came and told us they will upgraded the router with the best one on the market, the 'Nokia' router (guess nokia seels routers now) but it still the same issue

How to fix this problem? Look for better ISP? Who?? What to do man idk 😕

Edit: I forgot to add that my friend who literally lives 1 minute away has perfect speed and he has the same setup as mine