Understanding Express DCO and Can't Vote Final Review

Good day all,

We have been using custom change ItemTypes for years and I am trying to migrate us to Express DCO and Express ECO.  I am having a problem understanding how it is working and why I can't vote Approve in the Final Review activity.  I click on the Complete button, but nothing happens.  I can select Reject and it works.  Currently in the Change Control Board Identity I have CM and myself.  Neither one works for voting Approve.  Thanks for the help.