Maybe try emailing them again? Sometimes emails don't go through and get lost who-knows-where. I've had to re-send many emails over the years because of that exact reason. So yeah, maybe the best course of action would be to send a second email just to make sure they got it. Just make sure to be polite in it, though, in case the people in charge of registration did get the message but haven't had time to respond yet. After all, a lot of people have had questions for them lately.