How to begin diagnosing why internet not working?

[dasus]

AC86U stable firmware 8/11/2019 after downloading files for a few minutes it will say no internet in windows and the only resolution is to disconnect and reconnect the wifi at which it will magically work fine again. How to begin diagnosing the issue?

 

[ColinTaylor]

Log into the router and look at the system log.

 

[ApexRon]

...it will say no internet in windows and the only resolution is to disconnect and reconnect the wifi...

Let me restate:

• Everything works when all of a sudden your Windows PC says it lost access to internet
• You then reset the WiFi on the PC and then it finds the internet but will eventually lose it again

Correct?
Questions:

• Is this the only WiFi device with the issue?
• If you connect the same PC to the ASUS router with an Ethernet cable, do you still have that issue?
• Is the PC connecting via 2.4 or 5Gbps?

Answering these questions will determine next steps.