Oracle AP, making header description field required, as entering new invoice

Hi,

In AP creating invoice process, I need to know how can I convert some non-required filed to required ones.

My company transfers some invoice information in the description field on invoice header, and it is not came required as default, Are there any way instead of writing custom code (custom pll or form personalization), to make that field compulsory?

Thx,

Guney