Hi I'm getting a warning error while rendering my report, it says that 'Input string was not in a correct format.'

=SWITCH(

ReportItems!Textbox70.Value="2.2.PA" and IsNothing(Lookup(Fields!ProjectGUID.Value, Fields!ProjectUID.Value, Fields!PBSD.Value, "DataSet3")),1,

ReportItems!Textbox70.Value="2.2.PA" and Lookup(Fields!ProjectGUID.Value, FIelds!ProjectUID.Value, Fields!PBSD.Value, "DataSet3")="",2,

ReportItems!Textbox70.Value="1.1.PC" or "1.2.PV" or "2.1.PS",3)

It is for sure because, when I want to to know if Fields!PBSD.Value is = "" or not.

Any solution?

Thanks

Regards