Sorry to hear you are running into this issue. Does it happen with specific images only? In that case, you might want to check that it meets these requirements:
Formats accepted
JPG, PNG
Maximum resolution at import
8k x 8k
Maximum size at import
40MB
Maximum number of images that can be uploaded to a single page of a file
100
The app should be warning you if these requirements are not met, but we have a known bug that's preventing that warning from showing up.