Unity IAP iOS sign in issue. Asking for Apple ID, but not allowing user to do so

Hi,

I have integrated Unity IAP into my app and when I go to purchase a product a pop up appears displaying “Sign-In Required” asking for an apple ID and password with:

“If you have an Apple ID, sign in with it here. If you have used the iTunes Store or iCloud, for example, you have an Apple ID”

However, it only has an option to enter a password!

I have also noticed that this is the same message that is displayed when you are not previously signed in and click “Sign-In as existing user”, however when you do it like that, it allows you to enter a username and password.

Is this expected behaviour? Because I don’t know why it would ask you for an Apple ID and not give you an option to enter one.

Hi,

Yes, you should enter apple id and password. another option is to create sandbox tester from apple developer.
Here is the link to guide sandbox testing

thank you.