I hope policy is Active. Can you try evaluating policy by running refresh Identity cube task by specifying the specific policy Name to an user who is in violation of the policy and check if its working. If it works there it should work in access request.
It seems the Identity refresh is able to detect the violations but you only have issue with Access Request not detecting it. What is policyScheme set in your Access Request workflow that you have configured for your environment? I believe it should be interactive or fail for you to see the violations during the access request process.
I found that a policy violation is triggered during an access request only when the user is not in the policy violation list. Is this the expected behavior?
Policy Violation pop up occur for “Brace” in access request: