Check the "Sent" or "Private" subfolders if it's not in the main directory. :

: If you found this file name as a link on a random website or in an unsolicited email, do not download it . Malicious actors often use common WhatsApp file names to disguise malware or phishing downloads. Always verify the source on VirusTotal before opening unknown files. AI responses may include mistakes. Learn more

Open WhatsApp, use the function, and type "VID-20211221-WA0000". This may link you directly to the conversation where the video was originally shared.