Can't import files over 5 minutes in length

I’m unable to import 4k 30 fps video clips into FCP whenever they are longer than 5 minutes. Going a bit nuts over here.
Whenever I try, the background tasks icon whizzes around in half a second and nothing happens. I’ve successfully imported smaller clips up to 3 minutes duration. Anything longer than 5 minutes fails.
I’m using a Canon R6. Final Cut Pro 10.5.1. 2013 Mac Pro. My video library is on an external SSD with 400GB free space. The SD card in my camera is a 256GB ProGrade Digital SDXC UHS-II V60.
The clips are playable on the Camera, but I just can’t get them into FCP. I've spent a lot of time searching through FCP preferences to find what might be limiting my file sizes but to no avail. I’m hoping that I’m just doing something silly as I’m a bit new to video editing in general. This is my first post. Please help!

Not sure how you are importing, from the camera or from the card. I would suggest trying both ways. If you are trying to import from the camera, try instead copying the files from your card thru the card reader to your ssd and then import them from your ssd into FCP.

Thank you for your help. Unfortunately I don't have an external card reader. 

Fortunately I was able to solve the problem by installing the Canon EOS file transfer utility. This software allows me to import files from the card inside the camera to my hard drive via USB, and then I can add those files to my FCP library. 

For some strange reason I could not import directly from the camera card to FCP when the files are over 4GB. 

Because the manufacturers are still using FAT32 formatted card, which completely escapes. You would have thought by 2021 they would have moved on to at least ExFAT.