Did you add an account for you and for your child on the health app? That feature allows to log in to our chart with the hospital where you have your family doctor , I just log in there and download the app for my hospital then I sing up using and email address, once I get there I can see My chart I create a profile which gives the option to summit my vaccination card the one where it’s registered the two doses of the COVID vaccine, once the hospital receive that info they will verify and approve then from your chart app let’s say your hospital app you will see the option to export the digital vaccination card to health and wallet app like this once you link your account to health app you can see all your doctor results etc etc and in the immunization menu is where your vaccine info is registered after is exported, probably will allow to add more vaccines card to wallet