You didn't read the guidance...
localhost should work for the fictional numbers set in the console, but not for real numbers.
You didn't read the guidance...
localhost should work for the fictional numbers set in the console, but not for real numbers.
the warning in the firebase To prevent abuse, new projects currently have a sent SMS daily quota of 10/day. To increase this quota, please add a billing account to the project.
as there is limit 10/day then why it says
{"error":{"code":400,"message":"BILLING_NOT_ENABLED","errors":[{"message":"BILLING_NOT_ENABLED","domain":"global","reason":"invalid"}]}}
Because you have to enable billing.
Not quite sure what it is you want, your screen does not look like any of my screens in the first post?
Login success I want to save the phone number User UID
in Text for Label1
Not obvious where your problem is, you do not show the steps taken.
Where does this come from?
is it in your html, or in your app ?
Do you see this?

I would like to save the phone number and UID of the user in a database.
Screenshot not uploaded correctly either
I want to save the phone number and user ID in a label text.
I do not see this:

You get the userID (and the phone number) when the OTP phase is successful

If this is not working, then I might suggest you add the webviewextra extension to your app to enhance the webview, and see if OTP works then.
You could also test the html page in your computer browser.
I believe from seeing your blocks that you have the html file being served up from an online server, please also confirm you have correctly added all your firebaseconfig details.