Are you saying it produced no heroes whatsoever?
Please submit a support ticket to Small Giant detailing exactly what happened, and as accurately as possible, when the problem happened? That will let them investigate properly.
Here’s how to submit a support ticket:
Please make sure to press the “Support” button instead of the “Report a Bug” button from the in-game menu. If you need any further help, just reply to this post and I’ll do what I can.
Did you check your recent activity log to see if it shows there that you received it?