We have several iPads that will not do an update inventory. They don't respond. They have not updated for over a week. I have tried updating the IOS, They are stuck on iOS 11.2 - 11.26. But when you look at the device some of them that say 11.26 in the JSS are actually running 11.3 but the JSS still says 11.26. The devices that won't update inventory we are unable to scope apps to. The one's checking into the server do take apps. I have hard reset some of the devices, updated the inventory, sent blank pushes. None of this seems to help. They are stuck. Any help would be appreciated.
We had this same thing last week, we are running 9.100. I wrung my hands for a few days.... then a teacher requested a new auto install app so I pushed it to that grade level and those recalcitrant iPads installed and then updated the inventory. A hack but you might try pushing an auto install app to the iPad as that seemed to bump it from whatever loop it was stuck in.
What you are explaining does sound like the issue with pushing iOS updates to devices as mentioned by @jcline, when that command was pushed the device is updated but then responded with an incorrect response causing MDM to stop functioning, hence the JSS not knowing its updated.
Your options (other than wiping device) are to either update to Jamf Pro 10.3.1 or contact support for the database modification to clear out that bad response.
More information on what 10.3.1 resolved can be found here: https://www.jamf.com/jamf-nation/discussions/27775/jamf-pro-10-3-1-maintenance-release-now-available