Photo is still present after deleting it

Hello. 2 years ago the photo was delete it from the media folder and the post with it was delete too. The photo was protected by copyright. After deleting it I thought that everything is ok. Today I received a request for payment for using the photo…but I’m not using it. I even unable to see it in the media folder. I see the photo only when I’ll log in trought ftp.

Why the photo was not delete when I use delete buton in the media folder?

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