Uncaught Error: Call to undefined function createTitles ()

Good morning I am trying to create a function with php that fills in the title fields automatically, but when I try to pass the arrangement where I have my titles, I get the following error: "Uncaught Error: Call to undefined function createTitles ( ) ", Does anyone have an idea of how to solve it?

   $tituloHojaAlp = array('ID', 'línea', 'Modelo', 'Submodelo', 'Detalle1', 'Detalle2','Descripción','Compra Web', 'Formato', 'Moneda', 'Notas','Orden', 'Salto', 'Alcance', 'Amca', 'Hmx');

  function crearTitulos($objPHPExcel,$arrayTitulos){

     $columnasEx = array('A1','B1','C1','D1','E1','F1','G1','H1','I1','J1','K1','L1','M1','N1','O1','P1','Q1','R1','S1','T1','U1','V1','W1','X1','Y1','Z1'); 

     $long = count($arrayTitulos);
     $conColum = count($columnasEx);
     //ALP
     for ($i=0; $i <=$long ; $i++) { 
        if ($long == $conColum) {
           goto fuera;
        }else{
           $objPHPExcel->setActiveSheetIndex(0)  
              ->setCellValue($columnasEx[$i], $arrayTitulos[$i]);
        }
     }
     fuera:
  }


  crearTitulos($objPHPExcel,$tituloHojaAlp);