In the event, the guest contacts you because they were attempting their reservation online but then chose to call in. As a result, you are seeing X's in place of the empty space on the grid in Neptune. Because the guest put the reservation in their shopping cart, we have to wait for their time to expire to open up the space.
Instruct the guest to navigate to their shopping cart in Mercury and verify they have an item in their cart.
Once the guest has confirmed the reservation is still in their shopping cart, instruct the guest to click on the Cart.
This will bring the guest back to their shopping cart. From here, the guest can select Empty Cart at the bottom left side of the page.
A new window will appear and the guest will confirm they wish to Empty Cart.
Refresh in Neptune, and you will now see the site available for booking.