Invalid reference error in VBA

I'm beginning my foray into VBA and, not suprisingly, am now stuck.
The workbook is far too large to post, so here's some background:
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I'm receiving an error in my VBA at the point where I'm attempting to sort. This is the error message:

Run-time error '1004':
The sort reference is not valid.  Make sure that it's within the data you want to sort, and the first Sort By box isn't the same or blank.

My workbook consists of the following sheets:
Orders
SortSheet
Operations
Staging
BWInput
Analysis
Summary
I'm attempting to move/manipulate/sort data from the Orders & Operations sheets (via the SortSheet & Staging Sheets) to the BWInput sheet with this VBA:

Sub SetupOptimizer()
    ' Move two columns to a better location
    Range("Orders!Z:AA").Cut Destination:=Range("Orders!T:U")
 
    ' Move the block of raw orders data to the sort sheet
    Range("OrdersData").Copy Destination:=Range("SortSheet!E2")
 
    ' Get rid of the redundant data on the orders sheet
    Range("tblOrders").Clear
 
    ' Autofill the formulas down alongside the orders
    Range("SortSheet!A2:D2").AutoFill Destination:=Range("SortCodeDestination")
 
    ' Ensure the formulas run
    Calculate
 
    ' Sort the orders based on the formulas
    Range("tblSort").Sort _
        Key1:=Range("A2"), _
        Order1:=xlAscending, _
        Header:=xlYes, _
        OrderCustom:=1, _
        MatchCase:=False, _
        Orientation:=xlTopToBottom, _
        DataOption1:=xlSortNormal
 
    ' Move the sorted orders to the next step
    Range("SortResults").Copy Destination:=Range("Staging!A2")
 
    ' Put another copy of the sorted orders on the analysis sheet
    Range("Analysis!C9").PasteSpecial (xlPasteValues)
 
    ' Get rid of the redundant data on the SortSheet sheet
    Range("tblSort").Clear
 
    ' Autofill the formulas down alongside the sorted orders
    Range("Staging!Z2:EV2").AutoFill Destination:=Range("StagingCodeDestination")
 
    Calculate
 
    Range("tblStaging").Copy
 
    ' Replace the formulas with values
    Range("tblStaging").PasteSpecial (xlPasteValues)
 
    Range("tblStaging").Copy
 
    ' Move the resulting block of data to the BWInput sheet
    Range("BWInput!A1").PasteSpecial (xlPasteAll)
 
    ' Get rid of the redundant data on the operations sheet
    Range("tblOperations").Clear
 
    ' Get rid of the redundant data on the staging sheet
    Range("tblStaging").Clear
 
    ' Remove unnecessary rows from the Analysis sheet
    Range("AnalysisTrim").Clear
 
    Calculate
 
    ' Go to the summary sheet to finish
    Range("Summary!M17").Select
End Sub

Here are the Dynamic Range Names (DRN) I'm using:

AnalysisTrim  =OFFSET(Analysis!$A$1,COUNTA(Analysis!$C:$C)+7,0,10000,250)
OperationsHeaders =OFFSET(Operations!$A$1,0,0,1,COUNTA(Operations!$1:$1))
OperationsOrders =OFFSET(Operations!$A$1,0,0,COUNTA(Operations!$A:$A),1)
OrdersData  =OFFSET(Orders!$A$1,1,0,COUNTA(Orders!$A:$A)-1,25)
SortCodeDestination =OFFSET(SortSheet!$A$1,1,0,COUNTA(SortSheet!$E:$E)-1,4)
SortData  =OFFSET(SortSheet!$A$1,1,0,COUNTA(SortSheet!$E:$E)-1,29)
SortOrders  =OFFSET(SortSheet!$E$1,1,0,COUNTA(SortSheet!$E:$E)-1,1)
SortResults  =OFFSET(SortSheet!$E$1,1,0,COUNTA(SortSheet!$E:$E)-1,25)
StagingCodeDestination =OFFSET(Staging!$Z$1,1,0,COUNTA(Staging!$A:$A)-1,COUNTA(Staging!$1:$1)-COLUMN(Staging!$Y$1))
tblOperations  =OFFSET(Operations!$A$1,0,0,COUNTA(Operations!$A:$A),COUNTA(Operations!$1:$1))
tblOrders  =OFFSET(Orders!$A$1,0,0,COUNTA(Orders!$A:$A),COUNTA(Orders!$1:$1))
tblSort   =OFFSET(SortSheet!$A$1,0,0,COUNTA(SortSheet!$E:$E),COUNTA(SortSheet!$1:$1))
tblStaging  =OFFSET(Staging!$A$1,0,0,COUNTA(Staging!$A:$A),COUNTA(Staging!$1:$1))

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I don't know if it is the DRN that's causing the error, but I think I need to use one since the size of data block will change from run to run.
Any suggestions?