How can I add user info to conv.user.storage?

I'm using Actions Builder to create my chatbot and after user logins using Google I want to save his ID to storage variable. This storage variable doesn't exist on conv.user. So I do this:

if (conv.user.verificationStatus === 'VERIFIED') {
  conv.user.storage = {};
  conv.user.storage.id = str.rows[0].id;
  console.log("STORAGE");
  console.log(conv.user.storage.id);
}

But on Google Assistant it returns the error message and on my Webhook it's all good (no errors shown): Google Assistant Error

What can I do to save/persist at least my user ID for future referings?

Since user has the Google Sign In process done once, every time he enters in your action you have his info on the request (payload). It´s automatically added to user storage.

You should store it on conv.user.params and refer to it in your code.

You may have a get and set method to help you with:

getUserId(conv) {
    return conv.user.params.userId;
}

setUserId(conv, userId) {
    try {
        conv.user.params.userId = userId;
    } catch (e) {
        throw new error("Error setting USERID");
    }

    return userId;
}