Change Woocommerce Thank you page title

Hi,
I tried to change the thank you page title of woocommerce with several snippets like

function filter_woocommerce_endpoint_order_received_title( $title, $endpoint, $action ) {   
    $title = __( 'Vielen Dank - Sie sind angemeldet!', 'woocommerce' );
    return $title;
}
add_filter( 'woocommerce_endpoint_order-received_title', 'filter_woocommerce_endpoint_order_received_title', 10, 3 );

or

function wps_custom_thankyou_page_heading( $thankyou_title, $order ) {
    $thankyou_title = 'Vielen Dank - Sie sind angemeldet!';
    return $thankyou_title;
}
add_filter( 'woocommerce_endpoint_order-received_title', 'wps_custom_thankyou_page_heading', 10, 2 );

but nothing works. Any ideas?
Many thanks, Stefan