Over the past week or so I noticed Passbook show up in my battery usage. A few days ago it was 4% and it currently sits at 11% with low signal. The problem is I haven't opened that app in many months when I added in my Apple Store credit. I have its location setting off as well as background app refresh. The only recent change that occurred a couple weeks ago is I started family sharing in the App Store. Any ideas as to what could be causing this usage?