$query->bind_param

new_gist_file.php

if($stmt = $this->db->prepare("INSERT INTO messages (name,mail,message) VALUES (?,?,?)")){
			$stmt->bind_param("sss",$this->name,$this->mail,$this->message);
			$stmt->execute();
			$stmt->free_result();
			$stmt->close();
		}
		
		
		###########################################################
		
		
		$sql=("SELECT
      tbl_user.user_id,
      tbl_user.user_firstname,
      tbl_user.user_lastname,
      tbl_user.user_email,
      tbl_user.user_phonenumber
      FROM
      tbl_user
      WHERE
      tbl_user.user_archived = 0 OR
      tbl_user.user_archived IS NULL;
      ");
    if($stmt = $mysqli->prepare($sql)){
      $stmt->execute();
      $stmt->bind_result($id,$firstname,$lastname,$email,$phone);
      while($data = $stmt->fetch()){
        
      }
      $stmt->free_result();
      $stmt->close();
    }else{
      echo $mysqli->error;
    }