Calculating the driving distance between two addresses Google API

Question

This was always working with no problem until about a month ago when it does not calculate the distance anymore and show the error message instead. Any ideas on what is going on with this code and how to fix it?

function calcRoute() {
            var start = document.getElementById("start").value;
            var end = document.getElementById("end").value;
            var distanceInput = document.getElementById("distance");

            var request = {
                origin:start, 
                destination:end,
                travelMode: google.maps.DirectionsTravelMode.DRIVING
            };
            directionsService.route(request, function(response, status) {
                if (status == google.maps.DirectionsStatus.OK) {
                    directionsDisplay.setDirections(response);
                    distanceInput.value = 
                    response.routes[0].legs[0].distance.value / 1000;
                } else {
                //Show error message
                alert("Can't find road! Please try again!");
                clearRoute();
                }
            });
        } 

Answer 1

They started charging for it. You have to register at the following site, and start paying fees to use it:

https://developers.google.com/maps/documentation

Answer 2

I found the solution. I needed to enable (Directions API) to have it working again. Cheers!