I do not see that issue on my demo site. You can try to deactivate all plugins except Meta Box, MB AIO, and switch to a standard theme of WordPress. Or try to reproduce this issue in a fresh install of WordPress and let me know how it goes.
I believe it happened while duplicating some of the fields. It may have something to do with the duplication feature. Or, one of the fields got corrupted somehow and I duplicated it. Not completely sure.
I just deleted the fields that were giving me issues and rebuilt them. The new fields are working as expected now.