I am getting a url parameter (referrer) and then setting it as a cookie – this works great.

*I then want to retrieve the cookie value into a variable and then set the cookie value into the innterHTML and value of an input box. – this code (the retrieveReferrer function seems to do nothing). *

Where am I going wrong? and is their a tinder, simpler way to achieve all of this?

const queryString = window.location.search;
    if(queryString.length > 0) {
       const urlParams = new URLSearchParams(queryString);
       const referrerID = urlParams.get('referrer');
       setCookie('referrerID', referrerID, 1);
}

// Set a Cookie
function setCookie(cName, cValue, expDays) {
    let date = new Date();
    date.setTime(date.getTime() + (expDays * 24 * 60 * 60 * 1000));
    const expires = "expires=" + date.toUTCString();
    document.cookie = cName + "=" + cValue + "; " + expires + "; path=/"; 

}

function retrieveReferrer() {
   var StoredReferrer = getCookie("referrerID");
   console.log(StoredReferrer)
   var divElem = document.querySelector(".booking-referrer .el-input__inner").innerHTML = StoredReferrer;
   var divElem2 = document.querySelector(".booking-referrer .el-input__inner").value = StoredReferrer; 
}