Actions on Google new SignIn() is cancelling before user can give input

Question

We are creating an Action on Google using Dialogflow V2 API. We are using firebase cloud functions for our fulfillment and we are using an external rest api for our crud operations.

We have an undeployed action that I have tested in the simulator. The conversation flow is

1. The user is prompted to signin ie, new SignIn()
2. They are asked what they want to do and they respond
3. Their response is saved in our backend using their credentials

new SignIn() works in the simulator, but when I test on the Google Home Mini the SignIn() responds as if the user has rejected the propmpt to signin before they have time to respond

Is there some restriction regarding testing an Action that include Account Linking on the Google Home Mini?

The intent containing the new SignIn() is my Welcome intent, could that be causing the issue?

Here are the two intents handling SignIn(). Start Signin Intent is triggered by the Welcome Event

app.intent("Start Signin", (conv) => {
  conv.ask(new SignIn());
});

app.intent("Get Signin", (conv, params, signin) => {
  if (signin.status === "OK") {
    const payload = conv.user.profile.payload;
    conv.ask(`I got your account details, ${payload.name}. What do you want to do?`);
  } else {
    conv.ask(`I won't be able to save your data, please login`);
  }
});