Took some time but cleaned the top
"It took me a while to break the top all the way down but I finally got it with “minimal damage”. I love this tumbler but I was starting to get a smell from the lid soaking it in vinegar did not help I even bought a baby bottle brush kit to get in the hard to reach areas. But I said screw it im going to tear it apart. The hardest thing to remove is the lock with four tabs and as long as you can save 3 you should be good to go I found a pocket screw driver works best but a metal skewer and small fork worked as well after you pop that off push the center out and you’ll have 4 clear rubber pieces that you can’t mix up remove and clean and reassembly is a breeze"