What am I doing wrong? I filled them exactly as shown on card and in the video. They work perfect untill I vape them down to half full, then they start leaking. I did clean them before use as shown in the vid, and blew through them (as shown in the vid). Then saw on the item description page that it saws to not blow through them. Could this be the cause? Didn't seem likely though since they work great untill half full... Also, one of the 3 I've tried had the batt post issue. I pried it down a little. Thought I might have cracked it. The other 2 did not have the batt post problem, but also leak when they get down to being half full. Hating this! These are a great idea and I can really tell the difference in vapor production and taste. But I'm not gonna use them if they're gonna keep leaking. Don't wanna ruin my batts or get my pcc all sticky...