Lightroom Mobile is not importing all of my images

I do a lot of Hyperlapse videos where I need to import anywhere from 200 or more images to batch edit then export. I'm running into an issue where I will import say 300 images but when it's done importing, only 250 images get imported. Why are the other 50 not being imported? I usually will have to go back and manually import all the images that weren't imported initially. Then on export, I can only export about 30 images at a time for some reason. Is there a different workflow I should be using for importing and exporting?