SSRS IF statement when calculating workdays between two dates

Good day

I am having trouble with an If statement:
=IIf(IsNothing(Fields!Procurement_Final_Approval_Date.Value)
,

If Fields!Procurement_Final_Approval_Date is Blank - (it displays Error in the report field):
(DateDiff(DateInterval.day, Fields!Created.Value, Today())+1)
 - (DateDiff(DateInterval.WeekOfYear,Fields!Created.Value,Today())*2)
 - IIF(Weekday(Fields!Created.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Created.Value,1) = 7,1,0)
 - IIF(Weekday(Today(),1) = 1,1,0)
 - IIF(Weekday(Today(),1) = 7,1,0)
,
Else - (This section is working and displays a value)
(DateDiff(DateInterval.day, Fields!Created.Value, Fields!Procurement_Final_Approval_Date.Value)+1)
 - (DateDiff(DateInterval.WeekOfYear,Fields!Created.Value,Fields!Procurement_Final_Approval_Date.Value)*2)
 - IIF(Weekday(Fields!Created.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Created.Value,1) = 7,1,0)
 - IIF(Weekday(Fields!Procurement_Final_Approval_Date.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Procurement_Final_Approval_Date.Value,1) = 7,1,0)
)

Full expression:

=IIf(IsNothing(Fields!Procurement_Final_Approval_Date.Value)
,
(DateDiff(DateInterval.day, Fields!Created.Value, Today())+1)
 - (DateDiff(DateInterval.WeekOfYear,Fields!Created.Value,Today())*2)
 - IIF(Weekday(Fields!Created.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Created.Value,1) = 7,1,0)
 - IIF(Weekday(Today(),1) = 1,1,0)
 - IIF(Weekday(Today(),1) = 7,1,0)
,
(DateDiff(DateInterval.day, Fields!Created.Value, Fields!Procurement_Final_Approval_Date.Value)+1)
 - (DateDiff(DateInterval.WeekOfYear,Fields!Created.Value,Fields!Procurement_Final_Approval_Date.Value)*2)
 - IIF(Weekday(Fields!Created.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Created.Value,1) = 7,1,0)
 - IIF(Weekday(Fields!Procurement_Final_Approval_Date.Value,1) = 1,1,0)
 - IIF(Weekday(Fields!Procurement_Final_Approval_Date.Value,1) = 7,1,0)
)