Once you’re done inserting it, have you tried running your finger along the rim of the cup to ensure that it’s properly sealed? Usually when I do that, it doesn’t leak. (I also use the Lena large)

keep trying to position it. the key to the cup is a clean "suction". it needs to create a seal and the position of the cup needs to be "just right". it took me about 6 or 7 cycles to get a good consistent seal. maybe thats too long for some, but when you get a good seal, girl you dont have to worry about that thing from when you wake up to when you fall asleep. up to 12 hours of solid protection that leaves you feeling like you're not even on your cycle! its seriously so worth trying! I encourage you to keep trying for a good seal. if you grow too frustrated, you may need to try a different brand. you could call the comoany amd send back your old ones telling them they didnt work for you? maybe try for a refund... and get a different brand cup. you shouldn't be in the large in any of the cups unless youve had a child, so keep that in mind.

Maybe you didnt get it in deep enough? When it's been a long time since I used it I mess up thinking it's in place when it's not.