VBA Vlookup Formula MultiWorkbook

[Eudezet]

Dear Colleagues,

Using VBA I would like to search for values in other workbook using vlookup function. Others workbook name is not fixed, therefore I define variable string PYDN.

The problem is that if I change in code below file name to PYDN excel opens window and asks to choose a file.

Code:

Dim PYDN as string
PYDN = "Cloud.xlsx"

Range("I69").Select
ActiveCell.FormulaR1C1 = _
"=VLOOKUP(RC[-8],'[PYDN]SAPBW70_DOWNLOAD'!R69C1:R1651C7,5,0)"

How can I solve it? Please suggest.

Thank you!