Hello DiasDT-8403,
Thank you for posting in our Q&A forum.
For domain password policy, we must configure domain password policy within the "Default Domain Policy" group policy object, the password policy will take effect.
If we configure domain password policy in other custom group policy object instead of the "Default Domain Policy", it will not take effect.
Please check you configured domain password policy within the "Default Domain Policy" group policy object.
Also, please check whether you configured FGPP in your domain. Because if you have configured FGPP, the FGPP will have a higher priority than domain password policy.
For more information about FGPP, please read the link below.
Step-by-Step: Enabling and Using Fine-Grained Password Policies in AD
https://blogs.technet.microsoft.com/canitpro/2013/05/29/step-by-step-enabling-and-using-fine-grained-password-policies-in-ad/
Hope the information above is helpful.
Best Regards,
Daisy Zhou
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