[SOLVED] Connected, no internet for 5G on all devices

[Dodoegg]

My ISP is Plusnet, router is Plusnet Hub One.

Devices can connect to the 5GHz SSID when the SSIDs are split, but none can connect to the internet via 5GHz. The 2GHz line is fine, it's just the 5GHz connection causing trouble, and the 2GHz line is becoming very congested.

The wi fi has also begun dropping out periodically (just wifi, wired connections are fine), perhaps due to this congestion.

 

[kanewolf]

My ISP is Plusnet, router is Plusnet Hub One.

Devices can connect to the 5GHz SSID when the SSIDs are split, but none can connect to the internet via 5GHz. The 2GHz line is fine, it's just the 5GHz connection causing trouble, and the 2GHz line is becoming very congested.

The wi fi has also begun dropping out periodically (just wifi, wired connections are fine), perhaps due to this congestion.

Start with a factory reset of your router. Then set just the necessary passwords and SSIDs.
Double check. There could be problem with the 5Ghz hardware in the router.
Be sure to test with a laptop or tablet in the same room. Just because a device can pickup the router signal, does not mean it can transmit back. Device radios have much weaker signal than routers.