I believe the negative reputation has something to do with your posts. The "raffle" post was downvoted 3 times. Users seem to dislike posts with "unsanctioned program" and for explicitly soliciting SP or SBD. We earn these rewards by posting good contents giving value to the community. Soliciting or winning some SP or SBD without "proof of work" defeats the purpose of steemit.
RE: I have a negative reputation (-5) how to restore it to neutral