On iOS, if you manually delete a recording from Filmic Pro's internal library via the iOS Files app, then iOS may continue to store those files in a hidden directory for up to 30 days, before actually purging the files and freeing up space.
In Filmic Pro v7.4.2 on iOS, if we detect this hidden directory we will give you the option to purge this data and free up the space immediately.
You can also access this ability under Settings > Information > Empty .Trash Directory. However please note this option will only appear if this hidden directory exists on your device. If this option is missing, it means no hidden files are taking up space on your device.