不能两次使用update prepared语句

For some reason I can't use this statement... I always get this error: Fatal error: Uncaught Error: Call to a member function bind_param() on boolean in. I editing two columns so I have it twice.

My code:

        $id = htmlspecialchars($_GET["id"]);

        $stmt = $conn->prepare("UPDATE Notes".$_SESSION["id"]." SET title=? WHERE id=".$id);
        $stmt->bind_param("s", $stmttitle);

        // set parameters and execute
        $stmttitle = $title;
        $stmt->execute();

        $stmt->close();

        $stmt = $conn->prepare("UPDATE Notes".$_SESSION["id"]." SET note=? WHERE id=".$id);
        $stmt->bind_param("s", $stmtnote);

        // set parameters and execute
        $stmtnote = $note;
        $stmt->execute();

        $stmt->close();