After applying the policy assure that this policy is reaching the client .This you can verify by the policy sl. no
In SEPM go to clients tab select the group which you applied the policy select the details tab. Here you will be able to see the policy sl. no for that group
match this with the policy sl no. in the client both should be same
In client Open GUI go to help and support-----> troubleshooting here you will be able to see the policy sl. no