This question asks for the MV of a swap (as a mark-to-market) on one of the semiannual payment dates, so it’s a bit ambiguous (imo) as to whether the regular swap payment has been made or not. The question/answer doesn’t specifically say, but it assumes the payment has been made, so it’s excluded from the MV of the swap.
So there’s two payments on each scheduled payment date; the regular swap payment and a m-t-m payment.