Archer C2600 WIFI is not working

I posted a topic that my existing setup (wifi is not discoverable on any device mobile/tv etc. since last few days).
I upgraded to latest version few weeks ago, tried to play with some settings and now wifi has stopped:

Hostname	LEDE.2X.0.7
Model	TP-Link Archer C2600
Architecture	ARMv7 Processor rev 0 (v7l)
Target Platform	ipq806x/generic
Firmware Version	OpenWrt 21.02.3 r16554-1d4dea6d4f / LuCI openwrt-21.02 branch git-22.083.69138-0a0ce2a
Kernel Version	5.4.188
Local Time	2022-09-10 20:10:13
Uptime	6h 12m 32s
Load Average	0.37, 0.35, 0.33

I need to change my wifi from 5 GHz to 2.4 GHz or setup both to work.
I am little confused as well, on how to go back to original firmware.
Have downloaded original firmware (renamed same), got tftp client/server installed on Windows 10 PC as well, not sure what to do next.

I am not a networking techy, request to guide.

Your original topic remains visible. Maybe you could delete your original post to lock it.

In any event, follow below to at least provide the minimum info required relevant to your issue.

Please copy the output of the following commands and post it here using the "Preformatted text </> " button:
Remember to redact passwords, MAC addresses and any public IP addresses you may have:

cat /etc/config/network
cat /etc/config/wireless
cat /etc/config/dhcp
cat /etc/config/firewall

You mean this one?

If you're requesting the tutorial page: OEM installation using the TFTP method

Note: After firmware system upgrade and/or factory firmware installation, Both of the wireless, 2.4GHz and 5GHz are disabled by default. They need to be enabled by the user.

That's the first.