The sunroof has a two part seal, front 1/3 and rear 2/3. The seal is not designed to be water tight. More to direct 90% of the water away and seal out wind noise. The seals are about $120 from the dealer. You may have a blockage in the drain tubes that are at the corners of the sunroof opening. Try gently blowing them out with compressed air or use a wire to clean them out. (speedometer cable from your brother's motorcycle works good for this)