Hey Hannah,
thanks for your support! Yes, I cleared my cache. No changing. But I found a filter, that removes the subtotal field from the e-mails. The code goes to functions.php:
add_filter( 'woocommerce_get_order_item_totals', 'adjust_woocommerce_get_order_item_totals' );
function adjust_woocommerce_get_order_item_totals( $totals ) {
unset($totals['cart_subtotal'] );
return $totals;
}
Cheers!