This guide should help you downgrade the software on your LG TV so you can get root if you've updated to 3.30.10 like I did.

https://github.com/reprodev/LGTV-Firmware-Downgrade

I've tried to include as much information as I can and there are 3 methods to choose from on the GitHub. This has also been upgraded to let you know which file I used if you have the same TV model

This has been tested and confirmed to downgrade on an LG 43 Inch TV 2021 Model - LG-43UP75006LF https://www.lg.com/uk/tvs/lg-43up75006lf from Software Version 3.30.10 to 3.21.30 but should work on other LG TV models too with the relevant firmware for that TV.

Hope this helps and let me know if you've tried it