New PC is getting massive lag spikes in online games only

I just bought a new PC and when trying to play online games like CS2 or Valorant after a few seconds to a minute i'll start getting teleported back to where I was 5 seconds ago and/or disconnected from the match.

Single player games have been fine. I've been playing Indiana Jones and the Great Circle on max settings and not had a single issue.

My old PC and my PS5 don't have any issues playing online and although I checked my nat type and it was restricted I managed to set it as open and I was still having issues, I also have low latency and good download/upload speeds.

These are my specs:
CPU: Ryzen 7 9800X3D
GPU: RTX 5080
RAM: 32GB DDR5 at 4800 MT/s
Storage: IONZ G3 2TB M.2 NVMe SSD (I think)
MoBo: ASRock B650M-HDV/M.2

I bought it pre-built if that makes any difference.

I'm a bit of a noob hence why I bought pre-built but if the issue was hardware related surely it would affect single player games and if it was network related surely it would affect my PS5 but both are fine. Appreciate any help.