Did you set it as a “Single Disk - Resizable” image type? If so, were you creating a Windows 10/11 image?
We’ve had trouble with that lately and it turns out that Windows was putting a little partition after the main C partition on the disk. I think FOG tries to resize the last partition by default, so it ends up only resizing that small partition, thus it won’t end up fitting on any smaller disks.
To fix it we just removed that last little partition before capturing the image. I think it was just a recovery partition or something that we didn’t really care about.
Hope this helps!