Heya Cally, just want to clarify some stuff while I look into this more.
I took a quick look at the scorecards from yesterday and found two scorecards from you on the HB Suggested tour:
* The first scorecard shows you completed the 1st round in the event with a -4 (nice).
* The second scorecard shows you finished the 1st hole of the 2nd round of the tour
Did you only play the two games on that tour yesterday? If so, then it doesn't look like your score was lost, but rather UI the might have incorrectly reported that you returned to the 1st round when you did in fact move to the 2nd round of the tour.
Also, did you get a pop-up asking you to confirm joining your friend? If joining a friend requires either loading a new course or starting a new tour then you should always get a pop-up asking you to confirm. No popup means we just try and add your friend's scorecard to the existing game.