How to Waive Application Fee via Commonapp?

Hi guys,
I am on free/ reduced lunch at school so on the Common app i said I am eligible for a fee waiver. My counselor signed it sometime back… Today, I received a notification from a university that I need to pay my application fee or have a fee waiver. I am confused about what else I need to submit? I thought stating that I am eligible for a fee waiver meant I am able to apply to any common app school for free?

Call them and ask specifically what they are looking for to give you the waiver. Sometimes they want a certain box checked off on it. The counsellor does have to send a certain form.