Black video preview when paused and black rendering from iPhone video

[lukep74725403]

I'm trying to edit videos shot in portrait from my iPhone 12 Mini in the latest version of Premier Pro on the latest Windows. When I import the videos they are flipped widescreen and upside down. When I pause the video in the preview and on the timeline, the screen goes blank. When I export the video, I get audio only. 

[Ann Bens]

If the footage is variable framerate convert to constant framerate with Handbrake or Shutter Encoder before bringing into Premiere.