An Azure managed MySQL database service for app development and deployment.
@Ping S Thank you for reaching out.
If my understanding is correct you are trying to change your azure MySQL flexible server from private access to public access.
Connectivity method can't be changed after creating the server. If the server is created with Private access (VNet Integration), it can't be changed to public access (allowed IP addresses) after creation, and vice versa.
Please do also note: If the server was created with public access and later you want to change to private then you will need to use point in time restore Using restore to move a server from Public access to Private access
Limitations - Azure Database for MySQL - Flexible Server | Microsoft Learn
Hope that clarifies your ask.
Please do not forget to mark as accept answer if that answer your query.
Regards,
Oury