In the maintenance mode settings, I have set to allow shop manager permissions as shown in the image, but I cannot view the front-end pages, and when I try to view each page from the fixed pages, only the maintenance page is displayed.
Is there a solution?
Hi! 
It is working with all other roles?
Hi Daniele,
I have tried the subscriber, contributor, editor, and other permissions and was able to view the front end with all permissions except shop manager.