Gallery settings and Regular price not updated

I am using the WP Hotel Booking Plugin in 2 websites and I have the same problem in both of them

When I go to “regular price” and set a price from Monday to Sunday, then save, and then “update” and the changes are not saved so no price… Same error happens if I go to “Galley settings”, just select a couple of images, and the changes are not saved when I update the room….

Thanks a lot