where to check for self-approval configuration?

Hi there.

We've never intended to allow for self-approval. We are using PS delivered ERapproval process definition and the self-approval configuration on the step is exactly the same.

However, our users are able to approve their own expense reports in our production system. I tested in our QA system and it's the same case. My test in DEMO proved that users cannot approve their own expense reports by using PS delivered process definition.

I've compared our configuration in QA with DEMO. Looks the same to me. I attach my test doc for some expert opinion from the community. Where should I check so as to disable self-approval for expense reports?