Adjustment of Status - I-485

I applied for my son's Advance parole (I-131) along with mine in the same AOS packet. Our PD is May 5, 2020 [Chicago Field office]. We both had our biometrics together on 08/05/2020. I got my COMBO card in October. However, my son's AP is still pending. I raised two service requests but got no response. On 12/15/2020, I raised an expedite request for his advance parole stating that I need to take him to India to visit family. However, my request was denied today. The reason given was that his biometrics are pending. I called USCIS and told them that his biometrics were done on August 8, 2020 but the officer told me that for I 131 they need a separate biometric appointment. His biometric was for I 485. I am confused. Already, it's more than 8 months. Please suggest what should I do?