Dlookup not working

I have writen some code that will email customer with the products
they have ordered using tblOrderProducts

strItemsOrdered = strItemsOrdered & "Product CodeNotworking   : " &
DLookup("[ProductCode]", "tblOrderProduct", "[OrderNumber] =" &
("OrderNumber")) & vbCrLf & "Product Code   : " & CRS1.Fields
("ProductCode") & vbCrLf & "Product Name   : " & CRS1.Fields
("ProductName") & vbCrLf & "Qty            : " & CRS1.Fields
("Quantity") & vbCrLf & vbCrLf


The output is

Product CodeNotworking   : T1GN
Product Code   : C11
Product Name   : LCD TV
Qty            : 2


Product CodeNotworking   : T1GN
Product Code   : A8
Product Name   : Digital Camera
Qty            : 2

Product CodeNotworking   : T1GN
Product Code   : FREE
Product Name   : Free Gift
Qty            : 1

As u can seee Product CodeNotworking display T1GN on every item, this
should be the same as 'Product Code' also this customer has not
ordered a product with T1GN product code so not sure why its dispaying
this

Could your let me know what would be wrong

Thanks