I`ve been having 2 Ax2 router in my home network. One as GW, 2nd in my pc as client. Client is connected via 5GHz and 2.4GHz is using as another AP.
2nd Ax2 has set up fw with NAT because clietn bridge is not able anymore in ROS7.
I have the both MT with 7.6 ROS but I`ve found my 2.4GHz AP on 2nd Ax2(client) is not working. Wifi clients can see only 2.4GHz AP on Ax2(GW).
I tried to study some advices but There is no capsman, there is only wpa2 on and there is the same setup like in GW where 2.4GHz working properly.
I tried to upgrade 2nd Ax2 to latest ROS (7.11.1) with no changes. I tired to change Ap to client and run scan with no result.
It seems like 2.4GHz radio was off.
Unfortunately I don`t have another one available, only AC2.
This is my configuration.
[admin@Izba] /interface/wifiwave2> configuration/print
Flags: X - disabled
0 name="2.4" mode=ap ssid="izba" country=Slovakia security=test
channel.band=2ghz-ax .width=20/40mhz-Ce

Is this another issue or my device has broken 2.4GHz?

Draw a diagram have no clue based on words.

Ax2(GW+AP(2.4+5GHz))---Ax2(client(5GHz) + AP2(2.4GHz)). I`m not able to scan AP2 anymore.

What means "unable to scan AP2"?

Clients can`t see AP2 SSID anymore. If I switched AP2 to station mode I`m not able to scan any 2.4GHz APs, freq usage show me 0% at every channels. It seems there is 2.4Ghz radio broken.
Ok, I can try to use reset to default, setup ap in 2.4GHz, try it and if it works restore config back or setup all MT settings manually again. But My question is if is there some smarter way to fix it.

Change mode to ap ???

See my config file in 1st post.

Today I had interruption of power suply and then miracle happend...AP (SSID) is back.
But this ap was restarted because newest fw was installed but it need power off..not restart only.
Strange issue.

Current config looks like Russian roulette...it might work...or not.
You better set bandwidth to 20MHz (unless there are no other devices transmitting on the 2.4GHz band).
Next, you could better set the channel: either 2412, 2437 or 2462 (to have minimal interference.