@Джам Семенавна, Thanks for posting in Q&A. From your description, it seems there is conditional access policy configured in your environment which enforce the device to enroll into Intune when sign in the application. If there's any misunderstanding, please let us know.
And from your description, it seems to be failed when you enroll the device. Please let us know which platform we use. iOS or Android? Please ensure all the prerequisites are met and manual enroll the device with relative enrollment method to see if it can be successful.
https://learn.microsoft.com/en-us/mem/intune/fundamentals/deployment-guide-enrollment
Meanwhile, to enroll device into Intune, please ensure the user we use have Intune license assigned.
Please check the above information and if there's any update, feel free to let us know.
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