Reason of failed review:
Solder mask layer is opening entirely, If make according to below solder mask layer directly, the boards will be opening entirely without any solder mask to protect the boards.
Suggestions:
It will normally occur after generate Gerber file from Eagle, to avoid such issue, please make sure to cancel the tick of” Nagative Polarity” when generate solder mask layer. For details, here is the URL for your reference.