Premiere Pro - Video is lagging, audio OK

Hello there everyone, how are you doing?
This is my first question here, because I couldn't really find an answer to my problem.

I have this screen record that I did with my phone, it's about 15 minutes. It's basically a tutorial for some apps about planning astro photos, and, the weird thing is, the video goes perfect. Both in my android device as in my computer, but when I import the file to Premiere, it just goes tremendously slow. 
From time to time, it just jumps really fast and then comes back to being really slow again.
I had this issue a couple of times with some recordings, some go well, some don't.
The computer is not the problem by the way, I edit in 4K all the time, is just with these types of files that occur.
Any idea? I'm converting the file to a different format now, I'm not sure if it's an android issue, that maybe sometimes it just processes the file incorrectly or something from Premiere.

Hope you can give me some advice.
Thanks in advance.

Pablo.