JavaScript API Call not working

Hi there,
I have some problems in invoking the API to add a record to the table User Settings in my App (this is not the built-in User Settings table, instead it has been created by me).
I am getting a 404 error resource not found.
Note that the App, being a prototype, hasn’t been deployed yet. Should I?
Here my JS code (I have replaced {AppId} with my App’s ID and {AccessKey} with my App’s Access Key):

var apiUrl = '{AppID}/User%20Settings/Add';
var payload = {"Action": "Add","Rows": [{"Language": "bc9f3548", "Rental Point": "48d86e98"}]} ;
var options = {
	'headers' : {'ApplicationAccessKey' : '{AccessKey}',
			   'Content-type': 'application/json;charset=UTF-8'

	'method' : 'POST',
	'payload' : JSON.stringify(payload)
fetch(apiUrl, options)

It is applicationAccessKey (lowercase ‘a’ at the beginning, not uppercase).

What’s up with the ‘{AccessKey}’ part? I assume this is just a placeholder so you’re not exposing your key to everyone here? Just want to make sure you’re not using curly braces there.

It has been a while since I’ve experimented with it, but you might need the “Properties” object in your payload. I just use:

"Properties": {
      "Locale": "en-US",
1 Like

Thanks for the attention, @Marc_Dillon
Changed to lowercase the ‘a’ in applicationAccessKey, but didn’t help.
Yes: {AccessKey} is a placeholder, I am not using curly braces there. However I do put the key in the request header.
I also added the Properties dictionary, but didn’t help either.
I fear it might be something related to cross-origin resource sharing (CORS), but I have to study more before figuring it out…
Now I am testing the JS snippet in a static webpage. In the future, it will be hosted in a website, and I think I’ll need to put some attention to this.

Maybe I found the reason. Tried to integrate my App with Zapier, and I got this from Zapier:

Schermata del 2021-02-26 09-33-44

So one of my initial guesses was correct: my App is not enabled to accept API requests. Is there anybody in the AppSheet Team that can help me on this? Should I deploy the app?