Save raw Videosdk data to file

I am getting this error when I try to view the video after converting using ffmpeg.

To make then yuv file:
override fun onRawDataFrameReceived(rawData: ZoomVideoSDKVideoRawData?) {
if (rawData != null) {
fileChannel.write(rawData.getyBuffer())
fileChannel.write(rawData.getuBuffer())
fileChannel.write(rawData.getvBuffer())
}
}

To convert from yuv:

ffmpeg -f rawvideo -pix_fmt yuv420p -video_size 1080x1920 -framerate 25 -I input.yuv -f mp4 output.mp4

please help @chunsiong.zoom