How to delete a file which could not be recovered

[AC Question]

The problem with mobile repair shops near me is that they'll try to recovery data (like personal images, videos etc) every time they get a phone for repairing.

I need to give my phone for some repairs and I've a fear of them recovering my deleted personal contents which I don't like to share with someone and else appear on the internet.

What should I do? How do I delete images/videos that could not be recovered.

 

[dpham00]

There is not really a way, short of permanently destroying the phone. The only thing most people can do is a factory data reset