@Madison544 Thanks for posting in our Q&A.
It is by design. Based on my understanding, iOS and Android are the same. In android article, it also describes that Select Not required to disable the app PIN when a device lock is detected on an enrolled device with Company Portal configured.
From your description, did you mean that you don't need to enter PIN to access protected app when this android device is not enrolled, and it has device lock PIN?
If there is anything update, feel free to let us know.
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