iCheck('uncheck') works, but ('check') doesn't afterwards

[AndyatGAO]

Hi there,

I'm building a form which brings back a database column which is boolean and whihc is to be exhibited in a check box field. Here's the code:

function getMetricDetailList() {
    debugger;
    var MetricID = $("#metricDropDown").val();
    $.ajax
    ({
        url: '/Forms/GetMetricDetailList',
        type: 'POST',
        datatype: 'application/json',
        contentType: 'application/json',
        data: JSON.stringify({
            MetricID: +MetricID
        }),
        success: function (result) {
            $.each($.parseJSON(result), function (i, metric) {
                $("#firstbox").val(metric.MetricID);
                $("#secondbox").val(metric.MetricDesc);
                $("#thirdbox").val(metric.Description);
                $("#unitDropDown").val(metric.MetricUnitID);
                $("#calctypeDropDown").val(metric.CalculationTypeID)
                $("#orgDropDown").val(metric.OrganisationLevelID)
                alert("We are here.. " + metric.YearToDateAppropriateFlag)
                if (metric.YearToDateAppropriateFlag == true) {
                    alert("Truism");
                    $("#ytdappbox").iCheck('check');
                } else {
                    alert("Falsehood");
                    $("#ytdappbox").iCheck('uncheck');
                };
            })
        },
        error: function () {
            alert("Whooaaa! Something went wrong..")
        },
    });
}

when the form loads, the function works when YearToDateAppropriateFlag is TRUE and then when YearToDateAppropriateFlag becomes FALSE the box is checked then unchecked - but it is never checked again even when YearToDateAppropriateFlag bceomes TRUE again; the alert("Truism"); alert does fire but not the check statement beneath it.

Is there something that needs reseting there? I'm using the wrapbootstrap INSPINIA template by the way, is that affecting this?