App cannot be verified

We are using an iPhone app distributed as an AdHoc app, but an error message saying "App cannot be verified" was displayed. The error screen says, "Internet connection is required to verify the credibility of developer "Apple Distribution:●●●● CO.,LTD.(QQQ29B8GG2)"." When using this app, We are connected to the LAN, but not connected to the Internet.

If you temporarily connect to the Internet and start the app when the error screen appears, the error screen will disappear.

After that, when I switched from connecting to the Internet to connecting to LAN, it worked normally for a while, but after about 2 months, the same error screen appears again.

Please tell me how to resolve this error.

I believe that is working as intended.

How often does Apple verify AdHoc apps on iPhone? Is it once a year, once every 30 days, or every day?

How often does an iPhone app visit https://ppq.apple.com to verify trust? Is it once a year, once every 30 days, or every day?

Also, for AdHoc apps, do I still need to go to https://ppq.apple.com to verify trust?

App cannot be verified
 
 
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