Try to use the attached code. It only works fine if you run only on Mondays.
DECLARE @TodayDayOfWeek INT
DECLARE @EndOfPrevWeek DateTime
DECLARE @StartOfPrevWeek DateTime
SET @TodayDayOfWeek = datepart(dw, GetDate())
SET @EndOfPrevWeek = CONVERT(VARCHAR, DATEADD(dd, -(@TodayDayOfWeek-2), GetDate()), 112) + ' 07:00'
SET @StartOfPrevWeek = CONVERT(VARCHAR, DATEADD(dd, -(@TodayDayOfWeek+5), GetDate()), 112) + ' 08:00'
SELECT TOP (100) PERCENT dbo.CreateOrder.n_OrderOriginallyPlacedTime, dbo.Plu.Plu, dbo.Plu.ItemName, dbo.Plu.Price, dbo.t_OrderLines.n_Amount, dbo.t_OrderLines.n_OrderNum,
dbo.t_OrderLines.n_Type, dbo.t_OrderLines.n_MenuId, dbo.t_OrderPayment.n_Order, dbo.t_OrderPayment.n_PayAmount
FROM dbo.t_OrderPayment FULL OUTER JOIN
dbo.CreateOrder ON dbo.t_OrderPayment.nStoreID = dbo.CreateOrder.nStoreID AND
dbo.t_OrderPayment.n_Order = dbo.CreateOrder.n_OrderNum FULL OUTER JOIN
dbo.t_OrderLines ON dbo.CreateOrder.n_OrderNum = dbo.t_OrderLines.n_OrderNum FULL OUTER JOIN
dbo.Plu ON dbo.t_OrderLines.n_MenuId = dbo.Plu.n_MenuId
WHERE (dbo.t_OrderLines.nStoreID = '528') AND (dbo.CreateOrder.nStoreID = '528') AND (dbo.CreateOrder.n_StatusFlags <> '6') AND
(dbo.t_OrderLines.n_Type <> '26') AND (dbo.t_OrderLines.n_Type <> '18') AND(dbo.CreateOrder.n_OrderOriginallyPlacedTime BETWEEN
@StartOfPrevWeek
AND
@EndOfPrevWeek
AND (dbo.t_OrderLines.n_MenuId <> '2719')
ORDER BY dbo.CreateOrder.n_OrderOriginallyPlacedTime