Well, the least-effort path is, of course, factory-resetting your tablet (if it's new, chances are you haven't loaded too much data yet). If you don't want to try the reset yet, you could try to go to the Application Manager, "All" tab, find the Contacts app and, in there, clear cache and Data (don't worry, even if you had loaded contacts from Google, clearing Data will erase them but will also force the app to re-sync to Google, so your contacts would reappear in a few minutes).