I purchased an app through VPP and assigned it to one specific iPad in the JSS. Everything works properly with the exception of the app downloading to the iPad properly. When it comes time to install, the app stays in a pending status but other apps will download properly. 
Some of the apps that download properly say "Pending" as well. I went into the JSS and cleared the history of all failed apps and pending apps. 
Does anyone know why a purchased app would refrain from downloading vs a paid app?
Question
Self Service Purchased Apps status Pending.
+5+4i have experienced this when the devices enrolment has messed up somehow. removing the MDM certs and re enrolling has fixed the issue for me in the past, although its not as good as a full fix its been effective as a workaround for the issue
+6Do you have a caching server set up by any chance?
I am running into the same issue with pending apps and the thought just occurred to me that maybe our caching server is the bottleneck but I can't say for sure. I have tried doing a hard reset on some iPads and some have gotten apps but the majority still aren't getting it. We have 550+ iPads assigned and a lot still not getting all of their apps. It wouldn't be very feasible to unenroll and re-enroll all of the ones missing apps.
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