missing devices

I have an RT-AX88U as my main router with an RT-AX3000 as an AiMesh node, both running the latest stock firmware 3.0.0.4.386_49674 Over the last couple of days I have noticed that some of my 5GHz devices have stopped working and when I checked they cannot connect to the wireless. These devices...

All RJ45 cable. I like to use the traffic analyzer and also have a check on Qos Weblogg. I discover that my computer don't show up in the none of them, spite I can see it in the Network map (but with "Asus" as name). This happen for other devices connected to the TPlink splitter also. Is...