Yes.. it is working correctly... There can be few reasons for this..
PDP policy may not have been enabled. Once you publish a policy , you want to enable it.. (In IS 450 and 460).
There can be more than one policy in the PDP.. . Therefore your request may be effected with them...
When there are more policies, You need to consider about policy combining algorithm and policy order as well
Please find detail on working on XACML with WSO2IS from here