I am using Facebook API to log in a user. It logs in a user successfully.

But whenever I refresh the website or close it then reopen it logs out automatically. I don't need that I want a user logged in until he himself logs out of my website. How do I do it?

This is my code:

function statusChangeCallback(response) {


    if (response.status === 'connected') {
        setElements(true);
        console.log('Logged in');
        instaInfo();
    } else {
        setElements(false);
        console.log('not logged in');
    }
}

function checkLoginState() {
    FB.getLoginStatus(function(response) {
        statusChangeCallback(response);
    });
}

function setElements(isLoggedIn) {
    if (isLoggedIn) {
        document.querySelector('#fb-btn').style.display = 'none';
        document.querySelector('.logout').style.display = 'block';
        document.querySelector('.navigation').style.display = 'block';
        document.querySelector('.nav-main').style.visibility = 'visible';
        document.querySelector('#container').style.display = 'block';
    } else {
        document.querySelector('#fb-btn').style.display = 'block';
        document.querySelector('.logout').style.display = 'none';
        document.querySelector('.navigation').style.display = 'none';
        document.querySelector('.nav-main').style.visibility = 'hidden';
        document.querySelector('#container').style.display = 'none';
    }
}

document.querySelector('.logout').addEventListener('click', () => {
    FB.logout(function() {
        setElements(false);    
        console.log('Logged Out!');
    });
});