A link that worked yesterday may not work today. Video platforms change, and individual posts can be removed or made private.
Check the post first
Open the video in your browser. If it is deleted, private, region restricted or requires a login, the downloader may not be able to access it. Try the original public video link.
Try a smaller option
If a large file fails or takes too long, choose a smaller available quality and check your internet connection and device storage.
Give it another try
Temporary server limits can also cause a failure. Wait a little and try again. Some links simply will not be supported, and no downloader can promise every video will work.