LG OLED55CX3LA player totally useless - cannot play anything on my Plex Media Server

[m_dzhigarov_gmail_com]

Server Version#: 1.24.0.4930

TV: LG OLED55CX3LA
Player Version#: 5.21.1
Platform Version#: 5.2.3
WebOs: 5.2.3-290908

TV is wired with ethernet to my router, next to the Media Server.
All my devices are working fine - laptops, other TV (samsung), phones and so on.
My brand new LG sees the whole library of the Media Server, including photos, movies, tv shows.
Still, when I hit play - it starts buffering until I get an error: an unexpected playback error occurred

Even opening images doesn’t work. I have 500mbps internet at home, that’s not the issue.
Odd thing is that the TV player can play content from Plex.tv that is not hosted on my Media Server.

Please help.Plex Media Server Logs_2021-08-12_22-15-56.zip (2.2 MB)

Even pictures are not loading:

The server shows it’s streaming direct, over 21mbps but the tv is buffering

Here are more logs:
Plex Media Server Logs_2021-08-12_22-28-21.zip (2.2 MB)

Reinstalling the App on the LG TV doesn’t fix it either

[m_dzhigarov_gmail_com]

I am trying to play stuff with subtitles off, tried all sorts of movies and tv shows - nothing works. It just buffers until I get the error above. All apps are up to date.

[oposicionesmanuel_gmail_com]

Me pasa exactamente lo mismo, aunque tengo dos lg una de 55 y otra de 77, la de 55 no se conecta con el servidor que siempre lo ha hecho, espero tambien si me pueden dar una solución