Missing issued_to on IdToken after a performing a Refresh

[Markanime]

Hello, I'm using Google sing-in for a Unity app, but we send the IdToken that we receive to our server. on the server for security reasons we check issued_to variable (that contains the AppId) from the IdToken that Google reply us on Unity.

Performing a login it seems that works fine, but when we do a refresh sometimes google reply us a IdToken without the issued_to variable.

Do you know why is this happening ? is there a way to force google to send us always this value ?

Thank you so much