H4 Visa - Child 16 years old - Biometric is not appearing while booking USA Visa appointment

Hi I have a child who turned 16. I have a scheduled appointment for him in Aug 2023 in New Delhi. This appointment was booked last year. During that time, I did not see an option for his biometric appointment.

He is in US since 2016 and the Stamped visa expired in 2017, since then he is getting his H4 approved, but never travelled outside US.

Please suggest how do I get a biometric appointment for him. If I login I am only seeing one OFC appointment for him. If possible I would like to retain the August appointment date.