Without model number and manual that question is impossible to answer.
So collect that information and then ask the shop and LG customer service if it's by design, if you have to download new firmware or an app, or if your new TV is defective.
I have two LG smart TVs. One a 3D model which is around five years old and the second a 4K model which is six months old.
My older model can play .MP4 video files streamed from my network media drive yet the newer 4k model refuses to play anything other than .AVI
I've ripped my movies again into different formats including 264 .MP4 but I still get unsupported video format message when trying to play them to the TV.
I'm using 123 copy gold which ripped and converted files that work on the older TV.
Any ideas?

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