JS Socket.io: Client not catching event

I'm trying to integrate socket.io in my app, I will use it as a way to pass commands and real-time updates from server to client. I am able to connect both client and server and I'm also able to put the client in a room in which I will be emiting my events. However, the client doesn't seem to be catching events.

CLIENT-SIDE:

Connects client when window loads:

const socket = io("/");

socketConnect = function(){
    socket.on("connect", () => {
    	console.log(socket.id);
    })
};

window.onload = socketConnect();

Client clicks an upload button and form gets submitted, then client will wait for a confirmation from server:

(NOTE: This is a different .js file from the above code.)

submitForms = function(){

    socket.on("formOK", () => {
        console.log("form was sent");
        socket.disconnect();
    })

    document.getElementById("form1").submit();
}

SERVER-SIDE:

Gets connection and puts client in a room:

//initiates socket.io
io.on("connection", (socket) =>{
	clientID = socket.id;
	roomID = `ROOM:${clientID}`;

	//connects client to room where messages will be exchanged (room name = "ROOM:clientId")
	socket.join(roomID);
});

Server handles form and confirms success to client:

app.post("/uploads/kit-info", (req,res) => {
	//... handles post request

	//sends success confirmation to client
	io.to(roomID).emit("formOK");
	});

The problem:

Everything works fine but I am unable to get the "formOK" confirmation on the client-side. I've run tests and I confirm that the client is indeed in the room, so io.to(roomID).emit("formOK"); should be working, right?

I am not sure what is going wrong.

you are immediately invoking the socketConnect function instead of assigning it as a callback.

window.onload = socketConnect() 
window.onload = socketConnect //change it to this. 

in your submitForms function, you're registering the event handler for the "formOK" event inside the function. This means that every time submitForms is called, a new event handler is registered. As a result after the first submission, multiple event handlers will be listening for the "formOK" event. you can move the event handler registration outside the submitForms function and call it once when the client connects to the socket. update your client side code to something like this,

const socket = io("/")

socket.on("connect", () => {
  console.log(socket.id)

  socket.on("formOK", () => {
    console.log("form was sent")
    socket.disconnect()
  })
})

window.onload = socketConnect