@r.shoaib 

Can I have the link where did you get the latest 210203 version? You may check on the local website if there is a notice that this version can be downgraded to the previous version or not, if no, you can try to install the previous version on the router.

@r.shoaib 

There is no mention of this version cannot be downgraded to the previous, so you can give it a go.

BTW, if you want to troubleshoot the issue on the current firmware, we hope you could help verify some more info, such as:

1. How many signal bars on the same location when it is with a good reception before? You may try to modify the wireless settings on the router, such as changing the wireless channel, channel width, security to WPA20PSK, AES, reboot the router then confirm.

2. If this doesn't help either, try to reset the router to factory defaults, reconfigure it from scratch, then check again with the signal.

3. Kindly help verify the region version of the router, check the bottom sticker on the router, ensure it is the US version.