Hello, yesterday i upgraded to version 7.21.3 and today it stopped working, and I realized that the interface displayed “failed to set country” even though it had been selected. Has anyone encountered this error? I have Mikrotik hap AX3.
its usually cause by interference from the USB 3 Port.
For example a badly shielded USB Drive
I have had the hap ax3 for over 2 years and have been using the same USB port since then, and I haven't had any problems with it during that time, so I find it hard to believe in my case.
Ive just noticed that the 5Ghz died too which isnt usually caused by USB.
Do you have an US Model AX3?
I don’t know, i bought in EU
seems to be a common error: 7.21.2 "failed to set country" on hAP ax3 (both wifi1 and wifi2)
It was fixed in 7.21.3 
I encountered this problem for the first time today. Restarting the router hap ax3 helped. RouterOS version is 7.21.3.