Things happen fast at 99designs, so if a contest holder asks to see design changes, try to get them done as soon as possible.
This way, you’ll give yourself more time to show the contest holder you can produce the design they want — and you’ll keep their attention.
If you’re not clear about the feedback a contest holder has given, contact them to ask for more information.
On the other hand, less-than-positive feedback may be a sign that you should call it quits on this contest. Don’t worry, there are plenty of other contests to spend your time on.