Auto Rejection rule

Hi Team,

We have requirement of making journal and invoices attachments field mandatory, but unfortunately that functionality is not supported by oracle. So alternatively looing to write an auto rejection which helps while creating an invoice or journals with missing of attachment field leads to rejecting from saving the journal or invoice. As the current oracle is upgraded to spreadsheet is there any possibility of writing the rule through spreadsheet for both journal and invoice. Please help.

Thanks,

Neeharika.