Photoshop Elements 15 not showing preview/playing only sound for selected .Mov files

I recently installed PE15 and transferred some photos and .mov files from i-phone.

Some of the movies show a thumbnail picture and some do not.

The ones that show a thumbnail will play as expected (Sound and video)

The ones without a thumbnail will only play sound (no video)

The movies in question were taken on the same iPhone and over a 2-3 day period

I have tried refreshing the thumbnail and that doesn't work (thumb nail is not refreshed and still  will not work)

I am running windows 10.

Any help is appreciated.

Mike