@itay4 , Thanks for posting in Q&A. Based on my checking, in my environment, the "EAS activated" is with a boolean value. For your scenario the device without "EAS activated" value not showing when we check via List managedDevices, I suggest open case to check in the background to look into the issue. Here is a link with the steps to open case for your reference:
https://learn.microsoft.com/en-us/mem/get-support
Thanks for your understanding.
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