Storage Issue After Cancelling Video Transfer Between iPhone and iPad 10

While a factory restore might ultimately be necessary - and in so doing restoring your data from a backup - you might initially try a forced-restart of your iPad. The restart is benign - and will clear temporary cached data or incomplete data-files.

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

If the problem persists after performing the restart, it may be necessary to reset your iPad. Ensure that you have a current iCloud or iTunes backup before performing the reset:

How to back up your iPhone, iPad, and iPod touch - Apple Support

When you are happy to proceed, the next step is to reset the iPad to factory settings:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

When the factory restore has finished, you can restore your data from your backup:

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support