Yes, if you want to reserve ahead, because it’s filling up, then when you get OB, GS will give you an OBC.
Did the $78 fall off your CC, sometimes it shows pending, then falls off. I would take a screenshot of that charge on your CC for proof.
Since you don’t see it on the App, did you look on the travel summary in your cruise summary to see if it shows up there or on the DMW on the website version of the App?
Ridiculous this is still an issue. SMH