Bead question

I have a small 20ct desktop humi with 65% heartfelt beads in it. i cant seem to get the humidity down to 65, it stays at a rock solid 72%. I have been experienceing some burn issues with some of my cigars. My question is how do i get it down to 65%. I thought the bead were suppose to regulate that, but they are not or i made a mistake somewhere. I seasoned the humi right. i have calibrated my hygrometer several times. I sprayed the beads like the instructions told me to. Any help would be great

Tim