I've got
I've got this problem too with my OLED55E6V (AKA: the E6). I bought it in 2017. I find it baffling that a modern smart TV like has this problem. Built in obsolescence? LG should sort this out. I spent thousands of £ on this.
I have a Plex Media Server. I've tried the server and app settings to allow insecure connections but that isn't working.
Isn't this just a case of LG updating certificates?
The TV received a firmware update recently. Surely LG can resolve this?