Finding ffmpeg expert with youtube streaming

Hello, I made ffmpeg script that send video streaming, but faced the issue not to work with 1k and 4k video. I send video streaming on the below: 1. convert *.mp4 to *.flv(hd screen: 1920 * 1080) sudo ffmpeg -i [login to view URL] -acodec copy -c:v libx264 -preset medium -profile:v baseline -vsync cfr -s 1920x1080 -b:v 3000k -bufsize 3000k -threads 0 -r 30 -f flv [login to view URL]; 2. send video streaming to Youtube with the flv. SOURCE="" n=0 for f in $FOLDER/*.flv do SOURCE="$SOURCE -i $f" ((n++)) done ffmpeg -re $SOURCE -f flv "$YOUTUBE_URL/$KEY" But the video stream don't work on Youtube, Who can help me? I find real expert in ffmpeg script. Thank you.