SharePoint 2019 Multi Language for Public facing website

We have migrated a SharePoint 2010 public facing website to SharePoint 2019. Everything has been migrated and we are having issue with Language change. In sharepoint 2010 website we have a option for the public user to click and change the language.up on click we change the language using the below script but the same script is not working with SharePoint 2019 . We have already installed the language packs

function ChangeLanguage(){
//script fetches current display language
var lcid =_spPageContextInfo.currentLanguage;
//1025 language code for arabic
if(lcid.toString()!=1025)
{
var today = new Date();
var oneYear = new Date(today.getTime() + 365 * 24 * 60 * 60 * 1000);
var url = window.location.href;
//script changes current display language to arabic i.e 1025
document.cookie = "lcid=" + 1025 + ";path=/;expires=" + oneYear.toGMTString();
window.location.href = url;
}
}