I ca't install the AdHoc application on some iPads

hi,


I want to install the created application on the iPad with AdHoc, but there is a problem that only some iOS 9 and iOS 10 terminals can not be installed.


Specifically, when I try to install, the message below will be displayed.

Unable to download App.

"Appname" can not be downloaded at the moment.


I have 5 iPads I would like to install with AdHoc.

The result I tried installing:

* iOS 9 (9.3.5): NG

* iOS 10 (10.1.1): OK

* iOS 10 (10.3.3): NG

* iOS 11 (11.2.2): OK

* iOS 11 (11.4): OK


The following operation is performed for all terminals.

* Registering the UDID in the device and checking it in the provisioning profile

* When confirming that the registered UDID is included when unzipping the ipa file zip


What is the reason for not installing?