Iphone showing incorrect storage used

Hi,

I have an iPhone XS 512gb and recently deleted in excess of 22 000 photos on the device. I don't use iCloud photos and every photo were taken by the stock camera app. I do, however, use Google Photos to backup photos from the phone.

Anyway, when I deleted the photos I also opened the Recently Deleted folder and emptied that folder as well, in order to permanently delete the photos from the phone. Since then, I've also let it pass enough time in order for the photo to automatically delete the photos (>30 days). I've also rebooted the device several times.

Despite deleting all photos from the phone permanently (and rebooting and so forth), the storage space is displayed as such:

And:

And:

As you can see from the screenshots, both the phone itself and third party software (and Finder on my Macbook Pro) incorrectly shows that photos still take up >300GB (which it did before I deleted the photos), which is more than I use in total storage on the phone... The figure of free storage seems to be correct across the board, though.

Has anyone come across this before? Solution?