Detecting if a site is refreshed on a mobile phone

I developed this js code, that should detect when a site is loaded for the first time or is refreshed. I send this information tho a django view.
The problem is that it works on PC but not on mobile devices like phones, tablets, etc…
Here is the javascript code:

window.addEventListener('load', function() {
            // Check if the page has been reloaded
            var isReloaded = sessionStorage.getItem('isReloaded');

            if (!isReloaded) {
                // It's the first visit or a new session
                sessionStorage.setItem('isReloaded', 'true');
                // Perform actions for the first visit here
                
            }

            // Send the reload information to the server
            var isRefreshed = isReloaded ? 'true' : 'false';
            var csrfToken = '{{ csrf_token }}'; 
            $.ajax({
                type: "POST",
                url: '',
                data: {
                    'is_refreshed': isRefreshed,
                    'csrfmiddlewaretoken': '{{ csrf_token }}' // Include CSRF token for security
                },
                dataType: 'json',
                success: function(data) {
                    // Handle the response from the server here, if needed
                    console.log(data.message);
                },
                error: function(xhr, status, error) {
                    // Handle errors here, if needed
                    console.error(error);
                }
            });// Replace with your CSRF token
            // Make an AJAX request here to send 'isRefreshed' and 'csrfToken' to the server.
        });