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How to use Passwordless login with Auth0.Net



I have added the Auth0.AuthenticationApi to my Xamarin Forms project. I can see that the Client has a method called “StartPasswordlessSmsFlowAsync”. I have been trying to find a clear and concise example of implementing this but haven’t been able to do so. Has anyone had experience using this version of the API or have a link to a blog or tutorial?


From a look at the code that method maps to the /passwordless/start endpoint which would then require calling the /oauth/ro endpoint to complete the authentication.

However, /oauth/ro is considered a legacy endpoint and might not available to you depending on when you subscribed to the service; see

If you have that grant available then you would need to use the version of the library that still allows to call the /oauth/ro endpoint; that should be version 3 and the AuthenticateAsync method.