Integrate faceID/PIN code on existing IOS App

I am looking for a skilled mobile app development team that can help me integrate faceID or a PIN code into my existing IOS App. Currently, my app utilizes a username and password for customer authentication, but I would like to improve and add an additional layer of security to grant user access to their accounts. I have chosen to use FaceID authentication and will need help integrating it into my existing iOS App. Additionally, I need help with the API Integration because I'm unfamiliar with the process. This project requires a skillful team of mobile app developers with expertise in FaceID and API integration.
I only need help with the App itself. I will write the PHP script according to the output you need me to provide.