Also, I enabled UPnP. Solution B: Assign a Static IP and use DMZ. It still gave me a failed NAT type on PS.

@Joseph-TP I've done everything, closed the router and PS5 many times, but it isn't working. It gave me a "NAT type failed" error when activating WTFast, and when I search for online games, it...

I have a concern: Is it better for gaming to enable flow control and full duplex speed in my router?

I've subscribed to WTFast a bunch of times, but it's just not working for me. I even reached out to their team, and they think it might be a firmware problem with my GE800 TP-Link. I'm writing this...

@Vendex I can upload US firmware manually to my router (EU version).

@Kevin_Z Please provide the link for manual installation.