Thanks to @Dafydd if my post makes it through.
Thanks to @R. Proffitt for the quick replies (in comparison, no one's responded on my Plex thread yet)
According to the comments on another site (that I can't link to since it may be activating a spam filter that's preventing this post from being accepted), the only solution seems to reset the TV to it's factory settings.
If you have a newer TV that uses WebOS, I'll assume you can use R. Proffitt's solution regarding forgetting the network.
Good luck!
TV: LG Smart TV
Year: 2012 (I believe we got it before LG started using WebOS)
Model: 55LS5700-UA
Hi! While trying to solve another problem, I decided to test connecting my LG TV wirelessly to my router instead of through a WiFi extender.
Unfortunately, upon startup, my TV keeps connecting to my router by default instead of the WiFi extender and having to change networks (and re-enter the password) each time is a pain.
I even automatically sign in to a Smart World app -- as suggested on another thread to save info -- but no luck.
Any suggestions would be great!
Note
You can see a pic of my setup on the Plex thread I linked to above along with pretty much all info you could need!

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