Auth0 React Custom Domain

I’m using the auth0-react sdk and getting the following error when I tried to enable custom domains:

Issuer (iss) claim mismatch in the ID token; expected https://CUSTOM_DOMAIN.com/", found “https://REDACTED.us.auth0.com/

What am I missing?

UPDATE: I had to add the “issuer” to the Auth0Provider params and it works fine for login.

But now, it’s giving the same error when a user tries to sign up - except the error is reversed.

Issuer (iss) claim mismatch in the ID token; expected “https://REDACTED.us.auth0.com/”, found “https://CUSTOM_DOMAIN.com/”

Any help here would be much appreciated!