I think it’s possible this happens due to the way ACF attempts to cache meta.
When you crop an image the previous sizes still exists as image files in the uploads folder. And when you now attempt to get the new “large” size ACF finds the already cached values for the field which contains the old image URLs for the sizes.
Could you try playing around a bit with:
1. Updating the field group the image field is in. see if that changes things.
2. Remove the image from the field and re-add it.
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