bitrix-module/intaro.retailcrm/install/export/bitrix/js/intaro/sms.js

function getTimeRemaining(endtime) {
    return Date.parse(endtime) - Date.parse(new Date());
}

function initializeClock(id, endtime) {
    $('#countdownDiv').show();
    $('#deadlineMessage').hide();

    const timeInterval = setInterval(updateClock, 1000);
    const clock        = document.getElementById(id);

    function updateClock() {
        const time = getTimeRemaining(endtime);

        if (time <= 0) {
            $('#countdownDiv').hide();
            $('#deadlineMessage').show();
            clearInterval(timeInterval);
            return true;
        }

        clock.innerText = String(time).slice(0, -3);
    }

    updateClock();
}

function resendRegisterSms(idInLoyalty) {
    BX.ajax.runAction('intaro:retailcrm.api.loyalty.register.resendRegisterSms',
        {
            data: {
                sessid:      BX.bitrix_sessid(),
                idInLoyalty: idInLoyalty
            }
        }
    ).then(function(response) {
        $('#lpRegMsg').text(response.data.msg);
        $('#checkIdField').val(response.data.form.fields.checkId.value);
        initializeClock("countdown", response.data.resendAvailable);
    });
}

function resendOrderSms(orderId) {
    BX.ajax.runAction('intaro:retailcrm.api.loyalty.order.resendOrderSms',
        {
            data: {
                sessid:  BX.bitrix_sessid(),
                orderId: orderId
            }
        }
    ).then(function(response) {
        if (response.data.msg !== undefined) {
            $('#msg').text(response.data.msg);
        } else if (response.data.resendAvailable !== undefined) {
            $('#checkIdVerify').val(response.data.checkId);
            initializeClock("countdown", new Date(response.data.resendAvailable.date));
        }
    });
}