Update: we have been able to reproduce this, this is caused by your Adventure nodes being complete but the Adventure is not recognizing that- so it’s in a weird trapped limbo. This is caused by potentially exiting or getting an error and closing the game when on the reward screen of the last node.
(So for everyone else, recommend collecting all rewards from battles before closing PQ3)
The team is looking at just reverting the progress on the last node, so you’ll just need to claim the rewards again.
If that cannot be done they will need to revert the entire Adventure progress.
But then you’ll be able to play through and collect the rewards again (not too dissimilar to just replaying the Adventure).
The devs will be reverting this Adventure, so you’ll be able to play through it again and collect your rewards. In the meantime I have sent through the final reward to your inbox from your original playthrough as they were likely not collected.