I want to make different headers for my report from report builder. When I download report as PDF it shows me different headers for it, when I download it as .DOCX, the headers are the same.

I tried:
Adding two headers with different body and using: =IIf(Globals!PageNumber = 1, False, True)

I have tried the same header and using expressions: =IIf(Globals!PageNumber = 1, First(Fields!Contacts.Value, "dataset"), "")

None of that works for .DOCX.