Why doesn’t my new window close in the setTimeout event?

So I make a new window using the open method and later call a setTimeout method to close it after 5 seconds but for some reason it doesnt close. I have tried to replicate this bug in another file like this: let win = window.open(”); setTimeout(function() {win.close()}, 5000); and it works just as intended( closes after 5 seconds). But in here it doesnt and when I’ve put some break points it just skips it and the program ends.

            //Global variables
            const button = document.getElementById("btn");
            //Input-Fields
            const nameInput = document.getElementById("input-name");
            const phoneNumber = document.getElementById("input-phoneNum");
            const adress = document.getElementById("input-adress");
            //Variable
            let confWindow;

            function processInput()
            {
                //if statement checks if all fields contain something
                //or true, if not they are falsy
                if(nameInput.value && phoneNumber.value && adress.value)
                {
                    //New Window size and centering
                    let winWidth = 300;
                    let winHeight = 300;
                    let leftPosition = ((screen.width - winWidth)/2);
                    let topPosition = ((screen.height - winHeight)/2);

                    //String that contains onptions for the new Window
                    let options = "width =" + winWidth + ",height=" 
                                + winHeight + ", left =" + leftPosition
                                + ", top =" + topPosition;
                    //creates a new window
                    confWindow = window.open("confirm.htm", "Confirm Page", options);
                    confWindow.document.write("<p>Hi</p>");
                    setTimeout(function(){confWindow.close()}, 5000);
                }
                else{
                    window.alert("Please Enter Information in all fields");
                }
            }



            //Event Listeners
            if(button.addEventListener)
            {  
                button.addEventListener("click", processInput, false);
                
            }
            else if(button.attachEvent)
            {
                button.attachEvent("onclick", processInput); 
            }