@zawarq the clientid is different from your tenant name, and you havae auth0Options.ClientId for both client_id and tenant. ClientID is the application ID found here https://manage.auth0.com/#/applications and the tenant name is in the top right corner when you are in manage.auth0.com . The reason you are getting an error is because you did not put the correct tenant name in the parameters.
{"name":"ValidationError","code":"invalid_user_password","description":"Wrong email or password.","statusCode":400}
However I am sure of the user name and password as I they work fine with the Lock widget. Note that I also tried to change “username” to “email” and to “username/email” in the .AddParameter call.
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