CustomerPackage: UniqueID (INT); Reference (STRING)
Customer: FirstName (STRING); Surname (STRING); Email (STRING); Address (STRING)
PurchaseDetails: PurchaseDate (DATE); PurchaseDescription (STRING); PurchaseType (INT)

USE Example
GO

SELECT TOP 10

CP.Reference,
C.Surname,
C.Email

FROM CustomerPackage CP

INNER JOIN Customer C ON CP.UniqueID = C.UniqueID
INNER JOIN PurchaseDetails PD ON CP.UniqueID = PD.UniqueID

WHERE PD.PurchaseDate > dateadd(HOUR,10,getutcdate()) and PD.PurchaseDate < dateadd(DAY,29,getutcdate()) and PD.PurchaseType = 1

ORDER BY CP.UniqueID DESC

Reference   Surname     Email
1XX45       Smith       e.e@e.com
1XX45       Jones       f.f@f.com
1XX45       Betty       g.g@g.com
4B678       Reeds       h.h@h.com

Reference   Surname     Email
1XX45       Smith       e.e@e.com
4B678       Reeds       h.h@h.com