Index / match formula error

Dear All,

Anyone would you please help me on the below formula.

In the attachment, I need to get the exact value for each cell in 'Dashboard' tabs.. based on two values;

D4 = Combination of 'C4' & 'D2' + Goto 'BuyData' tab; If the values of Col B (should match Dashboard:C4) & Col C (should match Dashboard:D2) matches with 'Dashboard' tab then we have to pull the 'B.Qty' (col E)

I have filled some sample expected value...

It would be grateful if you could help me to find a formula for this.

Thanks.