Unable to access Siri AI even if the user is 13 year old.

My son is 13 years old today, but under his Screen Time Content & Restriction setting, the SIRI AI is still dark out(restricted) and the description below says: Siri is not available for users under 13 years old well the Apple Account clearly shows 13 years old. He really like the Siri AI but he couldn't access it. His device clearly supports Siri AI as I checked.