Newair humidor losing humidity

I purchased a humidor and seasoned it throughly exactly how it said to on the website. I keep it in the coolest/driest area of my home. I have the temperature set to 70 degrees and it never gets above 65. I have a 320 gram 84% boveda pack inside and the humidity never broke 74%. I haven’t open the door in a month and the humidity is slowly going down sitting at about 61% at the moment. I can’t sustain a constant humidity. I’m not sure what the problem is. It is a Newair250