Extension for Door View Cam possible?

Hi everyone, I have been really excited to join the Ring community and I purchased a Ring Door View Cam about a month ago from Amazon. Now I finally got around to installing it and ... it doesn't fit. I am literally missing less than 5mm, which is really annoying. I could swear that I measured the door before my purchase, but unfortunately, I must've made a mistake. Is there any way to fit this to a door that is slightly thicker than intended?