@Edu Fon,Thanks for posting in Q&A.
From your description, I know that you have set up the screen lock via Intune, but it was not worked.
Based on my researching, I found that GPO takes precedence over Intune policy, if the targeted device already token GPO, Intune policy will not take effect.
And you can run the command below with an admin account in CMD to check whether there existed Group policy on the targeted device.
gpresult /h C:\result.html
We suggest choosing either of them to manage the device.
Hope this can be helpful. If there is any update, feel free to contact me.
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