Problem with cors with chat component

Hi, i have a problem with cors policy. the problem is that I’m with localhost in both servers (front and back) the problem is that i get that error only with chat component.
I put the url in other component and works fine. I used postman to send a req and i get the response. Only with the component i get the error of cors policy.
Also I tried to put my token auth headers and didn’t work.
this is my code

import { JetView, JetApp } from “webix-jet”;

export default class windowChat extends JetView {

config() {
    


	const chatView = {
		view: "chat",
		url: `localhost:3000/chat`,
		calls: true,
	};

	let body = {
		rows: [
			chatView
		]
	};
    

	return {
		view: "window",
		localId: "win",
		body: body,
	};


}



init(view) {
    
	
	webix.attachEvent("onBeforeAjax", 
		function(mode, url, data, request, headers, files, promise){
			headers["authorization"] = 'token';
		}
	);

}

}

I think so the problem is the way the component makes the request or the fetch