When will to regain by top contributor thing?

Question

I had it before and lost it for some reason.

Answer 1

You had it because you answered a lot of questions in ONE category (probably a minimum of 40-50 in about 30 days), and of those answers, received at least 10% Best Answers. You have to maintain that balance to keep the Top Contributor badge. If you want it again, you need to answer lots in that category, and get enough of those answer chosen as Best Answer.