I can't find wifi SSID

I am using ar300m-ext router. Everything worked fine, I decided to update the firmware, downloaded it from the official site. Now I can’t find wifi ssid. I also cannot connect to the router panel ( The reset button doesn’t help. What can be done ?

Which firmware did you download?

Can you use uboot to reinstall the firmware?

Firmware can be download from GL.iNet download center

uboot guide Debrick via Uboot - GL.iNet Docs