Hello user2342,
Few things to check,
- It could expired tokens and regenerate the QR and try again.
- Make sure company portal app is up-to-date.
- Any conditional access policies inhibiting enrollment.
- Make sure the make/model supports Fully managed enrollment.
For further troubleshooting, follow this doc: https://learn.microsoft.com/en-us/troubleshoot/mem/intune/device-enrollment/troubleshoot-device-enrollment-in-intune?source=recommendations
Also have a look at the current known issues to confirm if your scenario or device doesn't fall under one: https://learn.microsoft.com/en-us/troubleshoot/mem/intune/known-issues
This is another reference that covers Android Enterprise enrollment troubleshooting: https://learn.microsoft.com/en-us/troubleshoot/mem/intune/device-enrollment/troubleshoot-android-enrollment
Hope this helps!
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