Person Management - One entry for the citizenship should be mandatory

Summary

One entry for the citizenship for a new hire should be mandatory - How can I customise the page easily?

Content

Hi all

I am a beginner with Oracle Fusion and a customer was asking if it possible to make the entry for the citizenship mandatory. I know how to make a single field required. But that doesn't work in this case. Has anyone an easy idea?

Kind regards

 

Matthias