When I tried to flag a question for moderator attention, even though I just flag once, it took away two of my flags. At first, it said that I have 11 flags, but when I flagged the question, it said I have 9 flags, so why did it take away two flags?
What is meta?
- Any Stack Exchange user can ask a question
- The community provides support, votes on ideas, and reports bugs
- Your voice helps shape the way Stack Exchange operates
The number of flags you have per day depends on your flag weight, which is a hidden number that increases when your flags get marked as "helpful" and decreases when they are rejected.
What likely happened here (as confirmed by Robert Harvey in a comment) is that while you were flagging, a moderator rejected one of your other flags, pushing your flag weight down enough for you to lose a flag.