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ffmpeg error when transmuxing from mkv to mp4

i have problem with output file generated from this command:

    `ffmpeg -i in.mkv -ss 00:20:00 -to 00:22:00 -c copy out.mp4`

When i ffprobe the out.mp4, i have this error:
“Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none, 1280×692, 2598 kb/s): unspecified pixel format”.
The in.mkv file with ffprobe present this:
`”streams”:
{
“index”: 0,
“codec_name”: “h264”,
“codec_long_name”: “H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10”,
“profile”: “High”,
“codec_type”: “video”,
“codec_time_base”: “1001/48000”,
“codec_tag_string”: “[0][0][0][0]”,
“codec_tag”: “0x0000”,
“width”: 1280,
“height”: 692,
“coded_width”: 1280,
“coded_height”: 704,
“has_b_frames”: 2,
“sample_aspect_ratio”: “1:1”,
“display_aspect_ratio”: “320:173”,
“pix_fmt”: “yuv420p”
Help appreciate thanks