Since ios16, any videos you have Copied to iphone, will not play, unless you first turn off wifi on the phone.
if you open a copied movie, you get the black screen with the controls, and the time bar shows 0:00 at both ends.
if you toggle off wifi with your phone and then open the video again, it works.
this is Very annoying to have to turn wifi off, open the app, start the video, and then toggle wifi back on for every video. is anyone else having this problem?