movies import & viewing

Hi, I have done what was mentioned in previous topics:  'in your iPhone, check the option Settings > Camera > Formats > Most Compatible to record new videos in the traditional (and compatible) MP4 format.'   

LRC uploaded the movies and deleted them on my camera as requested. But i still get the message: Lightroom has encountered problems reading this video.    Exporting  and viewing the movie in quicktime is possible without an issue...

- Converting the file from MOV into MP4 didn't help either...

- I am using the latest version from LRC on a mac catalina 10.15.6

WDYT?