This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
This is a normal thing -- in fact, I have yet to find a person that has been able to upload their assignment the first time they have tried! Consider it some extra time to exercise some deep-breathing and look at your assignment objectively one last time.