In my project I have a sheet that contains a list of names.
From a script, I copy a model sheet which I rename according to the names present in the list of names: no problem for that, including the copying of protections thanks in particular to the transferProtections function.
Secondly, I create a file per tab (with the same name): the copy goes without problem but the data protection is not copied.
Where is the problem ?
THANKS

const wbk = SpreadsheetApp.getActiveSpreadsheet();
const shModeleClub = wbk.getSheetByName('ModeleClub');
const shListeClub = wbk.getSheetByName('ListeClub');
const FOLDER_ID = ""; //noter ici l'ID du dossier qui va contenir les licences par club (apparait après /d/ ds l'URL)

function transfererProtections(sh1,sh2){
    // cas d'une protection de plages
    sh1.getProtections(SpreadsheetApp.ProtectionType.RANGE).forEach(p1 => {
      var p2 = sh2.getRange(p1.getRange().getA1Notation()).protect();
      p2.setDescription(p1.getDescription());
      p2.setWarningOnly(p1.isWarningOnly());
      if (!p1.isWarningOnly()) {
        p2.removeEditors(p2.getEditors());
        p2.addEditors(p1.getEditors());
      }
    })
}


//---FONCTION POUR CREER UN FICHIER CLUB INDEPENDANT AU LIEU DES ONGLETS - 
function creationClub1(){
let shClubLastRow = shListeClub.getLastRow();
let liste_club = shListeClub.getRange(3, 1, shClubLastRow -1, 1).getValues(); //la liste des clubs débute en A3
//console.log(liste_club);  
let valeurClub = liste_club.filter(String).length+1; 
//console.log(valeurClub); 
if (valeurClub%2 ==0){
  valeurClub=valeurClub/2;
} else {
  valeurClub=(valeurClub+1)/2;
}
//console.log(valeurClub); 

 let sheets = wbk.getSheets();

 let folder = DriveApp.getFolderById(FOLDER_ID);
 for (var i = 2; i<valeurClub ; i++ ) {
  let sheet = sheets[i];
  let name =  sheet.getName()
  fichierInitial = wbk.getSheetByName(name)

  if (!folder.getFilesByName(name).hasNext()) {
   let newSpreadSheet = SpreadsheetApp.create(name);
   sheet.copyTo(newSpreadSheet).setName(name);
   sheet.copyTo(newSpreadSheet).setName("Feuille 2");
   defaultSheet = newSpreadSheet.getSheetByName("Feuille 1");
   transfererProtections(fichierInitial,defaultSheet)

   newSpreadSheet.deleteSheet(defaultSheet);
   defaultSheet = newSpreadSheet.getSheetByName(name);
   newSpreadSheet.deleteSheet(defaultSheet);
   let newFile = DriveApp.getFileById(newSpreadSheet.getId());
   newFile.moveTo(DriveApp.getFolderById(folder.getId()))
  }
 }
}