- Go to Settings > General > iPhone Storage > Photos > try deleting the Recently Deleted album from this screen.
- If you delete many photos simultaneously, wait until the process is complete. You can also try deleting the photos in small batches.
- Try disabling auto-lock to prevent your iPhone from getting locked while the album is being deleted.
Fix 1: Use Alternate Method to Delete the Album
Go to Settings > General > Storage > select Photos from the list > tap on Empty Recently Deleted album.

Fix 2: Delete Photos in a Batch
Try deleting the photos in smaller batches instead of deleting them all at once.
Go to the Recently Deleted folder > tap on Select > select photos in small batches > delete them.

Fix 3: Turn Off Auto Lock
When your iPhone locks before the Recently Deleted album is emptied, the process is interrupted. Therefore, consider disabling auto-lock temporarily and deleting the photos.
Go to Settings > Display & Brightness > Auto Lock > select Never .

Fix 4: Delete Using iCloud
If the Apple Photos app fails to delete the photos, use the web version of iCloud. For that, visit icloud.com/photos . Log in with your Apple account > go to Photos > click on Recently Deleted > Delete All .
Note: This only applies to photos synced to iCloud.
