Unable to import MP4 Media

Hi Guys I'm a total newbie here so please forgive me. If this is a lame question, I've tried searching but can't find anything that relates to my problem. I suspect it is a user error (down to me). But after two hours of searching and changing some settings still no Joy. I am trying to edit my Drone footage with little success.

I have made one video with no problems edited it, even added an audio track. I then decided to have another bash. I, therefore, started with New Library/new project. named it local. 

I then try to add media and my collection of MP4 vids are all ghosted. the only media available is 2 .jpg files. See attachment

For Info: I'm using FCP 10.4.3 All my files are on an external hard drive, named studio, having been downloaded from the MicroSDHC Card. I have other folders with MP4 files, on the same external hard which were taken on my iPhone using My DJI Osmo3. I can import these, but not the MP4's from my Mavic Pro and I have not changed any settings on my Mavic Pro. 

I suspect I'll kick myself when someone points out my error  

Hi Guys 

Problem solved: so I thought I'd post an update just in case anyone else has the same issue. with their Mavic and just happen to be using an older version of FCP. The issue was H265. Final Cut Pro 10.3.4 cannot Handle H265. So I may have to look at investing in a newer MacBook. When set to H265 you cannot select DLog-M or HLG in colour mode in the DJI Go App. Not sure if this is detrimental just yet. Given I always enhance saturation and a few other settings anyway. Also when set to H265 I can still import to Premiere Pro. Therefore if I do need H265 Premiere Pro will do for the time being. I'm therefore in no rush to run out and spend £1.5K on a laptop to do the job. find my feet first with FCP then new equipment