"No IUserTokenProvider is registered." When calling UserManager.GeneratePasswordResetToken In OWIN Identity.

I tried to generate a password reset token with the following code:

            string Id = UserManager.FindByName("userName").Id;
            string code = UserManager.GeneratePasswordResetToken(Id);

This resulted in the error "No IUserTokenProvider is registered." More details:

[NotSupportedException: No IUserTokenProvider is registered.]
   Microsoft.AspNet.Identity.<GenerateUserTokenAsync>d__e9.MoveNext() +287
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +144
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +84
   Microsoft.AspNet.Identity.<GeneratePasswordResetTokenAsync>d__4f.MoveNext() +363
   System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +144
   System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +84
   System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() +49

Can anyone explain what is required here?