@James Chan_110 , Thanks for posting in Q&A. From your description, it seems you are unable to login Intune after configuring the conditional access policy to require device compliant. If there's any misunderstanding, feel free to let us know.
Firstly, we suggest login on a compliant device and remove the conditional access policy we configured. Then configure the conditional access for some test users and only select the cloud app we want like office 365.
If there' any update, feel free to let us know.
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