Without further details… this could be many things.
Let’s start with verifying if your TV’s LAN port supports 100 Mbps or faster bandwidths – 100 Mbps might not be fast enough to stream 4K content reliably.
Beyond that… your CPU seems to have a PassMark score of approx. 11850. That’s a good score but not fast enough to transcode 4K content, e.g. if your TV cannot deal with the media as-is (sometimes this can happen if your TV doesn’t support a certain codec or a combination of codecs in your files). You’ll need a PassMark score of 12000 to transcode 4K SDR content. For 4K HDR content you’ll need a score of 17000.
If you have enabled hw-accelerated streaming, your GeForce RTX 3060 should be able to handle the transcoding for you – however there’s use cases where the GPU cannot do that (e.g. when it comes to burning subtitles into the video stream.