You need to provide more information if you want your prestige to be restored.
First, I can't even see your name on the screenshot you provided. It could be from anybody.
Moreover, as you can see on your stats page, you have played only 8.6 hours on KTK:
3xP' Statistics ~ « Player Details
When I saw you in-game, you were prestige 3, and you're asking for prestige 11. It would mean that in 8.6 hours, you earned 14 or 15 prestiges. Which is clearly not possible.
Or maybe you have changed your CD-key? If yes, you need to write here your previous GUID, so that I can find your previous stats page and check your stats.
If you don't remember your previous GUID, you can at least give me previous names you used, so that I can find your stats page.