how to check date

dateDiff.js

function dateDiff(startDate, endDate) {
    console.log(new Date(startDate), "startDate"); // since user register
    console.log(new Date(endDate), "endDate"); // date of voucher expired

    const diffInMs = new Date(endDate) - new Date(startDate);
    const diffInDays = diffInMs / (1000 * 60 * 60 * 24);
    console.log(diffInDays, "diffInDays");

    if (diffInDays === 5) {
        console.log("voucher disappear");
    } else {
        console.log("voucher still appear");
    }

    return diffInDays
}

const startDate = '2023-02-11';
const endDate = '2023-02-16';
dateDiff(startDate, endDate);