Request page coding problem of a report.

Hello Experts,

Right now I'm working on a report. I have taken two DataItems: Item Ledger Entry & Item Journal Line. Now I need to set four request page filters i.e. Item No., Location Code, Entry Type, Posting Date(Start Date, End Date).

For that I have taken five variables in C/AL Global i.e. Item No.(Code), Location Code(Code), Entry Type(option), Start Date(Date), End Date(Date).

I have also declared those fields on Request Page Designer.

Now I have written the following code:

Item Ledger Entry

---

OnPreDataItem():

SETRANGE(Item Ledger Entry.Posting Date, Start Date, End Date);

SETRANGE(Item Ledger Entry."Item No.", "Item No.");

SETRANGE(Item Ledger Entry.Location Code, Location Code);

SETRANGE(Item Ledger Entry.Entry Type, Item Ledger Entry.Entry Type :: "Negative Adjustment");

The code has run but whenever I enter any values on the request page the report doesn't shows any data. If I left those fields empty the report shows all the data. I have no clues how to correct it. Please Help me!