Luckily, the problem is non-fatal, in that it doesn't corrupt your save (if you reload, you're back at the point right before you tried to claim the reward), and there's a slightly crocky workaround which I haven't tested myself, but if you're playing, you might want to hold off on that last reward screen until Hello comes up with a fix. The Expedition is slated to run for several more weeks, so hopefully there's time to get that done.

--G.
-><-
Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
zgryphon at that email service Google has
Ceterum censeo Carthaginem esse delendam.