This question is an exact duplicate of:
I saw I lost some reputation over on Parenting due to a removed user. Nothing unusual there.
Until I saw the details.
But it looks suspiciously like the 6 separate -2 rollbacks were added together for another full -12 rollback.
Is that what happened?
I'd like to note that a -12 is not impossible, but — knowing my voting history on that Stack — it is implausible.