Expression Builder in qualification plan not allowing to add or edit

Summary: I am learning absence management. I am in Oracle Learning, and I am following along. However, the teachings are in responsive and we are in Redwood. I have created my qualification plan, and am now working on creating the qualification band matrix. Yet there is no where for me to Add/Edit the expression it wants me to build.

I followed the steps of creating the plan first, save/close. Then go back in to edit/add the matrix. Am I missing a step?

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