First of all, if you don't state your nationality/passport, it is not possible to comment.
Secondly, if a U.S. passport, state which Brazilian Consulate has jurisdiction, as regs for each are a bit different and each is a bit different in level of cooperation with questions.

Nowadays, a U.S. passport holder no longer needs to use a new Brazilian visa within 90 days of issue. When exactly was your visa issued? What exactly does it say on it?