Open the Photos app
Tap Albums
Scroll down to Utilities
Tap Recently Deleted
Look for the deleted video
Tap the video
Tap Recover
Confirm Recover
Check the Hidden album
Open the Photos app
Tap Albums
Scroll to Utilities
Tap Hidden
Look for the video
Check iCloud Photos
Go to iCloud.com
Sign in with your Apple ID
Open Photos
Check Recently Deleted
Check the Files app
Open Files
Tap Browse
Check Recently Deleted if available
Check On My iPhone and iCloud Drive
Check other apps
Open Messages
Open WhatsApp
Open Google Photos
Open Dropbox
Check for saved copies or backups
Restore from an iPhone backup
Open Settings
Tap General
Tap Transfer or Reset iPhone
Restore from an iCloud backup if available
Restore from a computer backup
Connect iPhone to a Mac or PC
Open Finder or iTunes
Restore from backup if available