Make sure your applying enough pressure by vent or its all pointless!
Press down firmly, Grap tail and i often will pull back to relax it, so it looks like a upsidedown U i guess? Then i grab and not push but roll (like toothpaste almost) But again it all matters on your hand applying pressure at the vent! Do 2-3 times (then switch if no avail, OR hey maybe ur oddgods hit and they all females)