After troubleshooting for 2 days I fixed the problem. Need to set WDS Mode to 1 instead of Auto. See screenshot image below. But this WDS Mode is available in Archer C7 firmware 1.0.3 and hardware...

@Tony I just tried with 5Ghz, apparently it doesn't work cos the 5Ghz WDS can't find the main router, presumably it's using 2.4Ghz bandwidth.

@Tony No, I'll try the 5Ghz now. But the 255.X is set by the main router. I reckon we need to follow the IP from the main router, am I correct? The main router is a loaned device with SIM card...

I was a proud owner of 6 TP-Link WiFi routers. But now I have an issue with my new Archer C7. I want to have truly mobile Internet connectivity and I want to use Archer C7 (AC1750) as a bridge to my...