Button click data-bind is not working with knockout - asp.net-mvc

Question

I cannot get the following piece of code to fire the button click to call save. I am using ASP.Net MVC with Knockoutjs. I am new to knockout and mvc. What am I missing here? Thanks in advance.
cshtml
#section scripts
{
<script src="~/Scripts/knockout-3.4.0.js"></script>
<script src="~/Scripts/knockout.mapping-latest.js"></script>
<script src="~/CustomScripts/bookingviewmodel.js"></script>
<script type="text/javascript">
var bookingViewModel = new BookingViewModel(#Html.Raw(data));
ko.applyBindings(bookingViewModel);
</script>
}
<div class="content">
<button class="btn btn-primary pull-right" data-bind="click: save"><i class="fa fa-check"></i> Save Booking</button>
</div>
bookingviewmodel.js
BookingViewModel = function (data) {
var self = this;
ko.mapping.fromJS(data, {}, self);
self.save = function () {
$.ajax({
url: "/Booking/Save",
type: "POST",
data: ko.toJSON(self),
contentType: "application/json",
success: function (data) {
if (data.bookingViewModel != null) {
ko.mapping.fromJS(data.bookingViewModel, {}, self);
}
}
});
}
}