I'm trying to decrypt one webm video file using shaka, but getting Cannot parse media file error.

INPUT:
Code:
shaka in="Niksh Chh.S01.E03.720.DRM.webm",stream=video,output="Niksh Chh.S01.E03.720.webm" --enable_raw_key_decryption --keys key_id=06096b2215a6463f951b6e687b87c0cf:key=ff66b86ebabe06b2f3301eb3601d9ad9
OUTPUT:
Code:
I1031 07:38:19.264371   16528 demuxer.cc:94] Demuxer::Run() on file 'Niksh Chh.S01.E03.720.DRM.webm'.
I1031 07:38:19.278464   16528 demuxer.cc:160] Initialize Demuxer for file 'Niksh Chh.S01.E03.720.DRM.webm'.
E1031 07:38:20.189749   18536 packager_main.cc:628] Packaging Error: 8 (PARSER_FAILURE): Cannot parse media file Niksh Chh.S01.E03.720.DRM.webm

How to fix?