Mine didnt seat all the way when I put in the first time. I pushed it on a little harder and it popped all the way in. I dont know if you have the same thing or not. If you have the cap screwed all the way down to the 25Nm(?) it should be seated. Did you pull it back out and check it? I would think it might be squashed a little if you didnt have it seated all the way. Or it just might have seated when you tightened down the cap.

MikeR