Sign in with apple, getting response invalid client

Hi

I am trying to make my web app to use 'Sign in with apple'

I did following preocedure but I keep getting 'invalid client error'

Could you help me please?

1. created AppId and check Sign in with Apple

2. created ServiceId

3. linked AppId with ServiceId as a primary App Id

4. created sub domain, domain and redirect url

5. created Key and check Sign in with Apple

6. linked Key with AppId

7. I wrote some example code from pages below

https://developer.apple.com/documentation/sign_in_with_apple/sign_in_with_apple_js/configuring_your_webpage_for_sign_in_with_apple

Could you please tell me what I did wrong?

I have been wasting my time for a couple of days.

Please help me. Thank you.