This usually means the server requires a "User-Agent" or "Referer" header. You can add these in FFmpeg using -headers "Referer: https://website.com" .
If the m3u8 file contains an EXT-X-KEY tag, the video is encrypted (DRM). Most standard tools cannot download these without the decryption key, which is often protected.
Always ensure you have the legal right to download the content before proceeding.
To download video content from an .m3u8 playlist—which is the format used for —you need a tool that can fetch the individual video segments and merge them into a single file (like an .mp4 ).