Youre only showing how to open the HIDDEN FILES FOLDER. But the reall problem here is the Contents/Files in the HIDDEN FILES FOLDER are missing or deleted by miui in some way.

I have Mi 9T and im in shook to finding out my files were gone. I was about to transfer them from my mobile to my pc. But sadly, for some unknown reason those files/data were gone.

I'm also facing the same and it's very disgusting and frustrating at the same time. I had some of her pictures left which were my reason to live in this cruel world are completely gone and I'm empty handed right now. :)
Thank you Xiaomi, your shitty codes ripped my life