Passport trapped in limbo. "Additonal information needed" on renewal. No letter telling me what info is needed. No help via hotline or email. Incredibly frustrated -- help!

I submitted my passport renewal application by mail on December 9th, it was marked as received December 24th. On Friday, January 17th I received an email stating Application Status: Additional Information Needed.

It said I would receive a letter or email within one week stating what information is needed. Fast forward one week, no letter received via mail or email. I've called the passport hotline at least 3 times and they said they can't tell me over the phone what is needed, they can just request another letter to be sent to me. I tried contacting both [[email protected]](mailto:[email protected]) and [email protected] over email and they said "To better assist you and due to general email security restrictions, we are unable to provide you with any specific information regarding your particular situation.  Please call our office at the number listed below."

I feel like I'm going insane! Is there a way to actually reach someone who can help me so my passport isn't trapped in limbo forever?!