macros should run based off of drop down menu change, is failing to run

ITraining Stats, upload version.xlsm

I have this macro which should insert data from the Calculator sheet to the appropriate sheet based off of whatever sheet name is selected from the drop down menu at cell Z18 of the Calculator sheet. However, selecting any sheet name from the drop down menu fails to make the macro run. What am I doing wrong?

Sub exporttoexercisesheets()
'
' exporttoexercisesheets Macro
' This will export R1:R19 to the exercise sheet selected in the dropdown meanu at Z18.
'
Select Case Range("Z18")

Case "Prime Bench Main"
Sheets("Prime Bench Main").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
    
Case "Prime Bench Assist"
Sheets("Prime Bench Assist").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
     
Case "Prime Bench Supp"
Sheets("Prime Bench Supp").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
      
Case "2ndary Bench Main"
Sheets("2ndary Bench Main").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
   
Case "2ndary Bench Assist"
Sheets("2ndary Bench Assist").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
     
Case "2ndary Bench Supp"
Sheets("2ndary Bench Supp").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
      
Case "Squat Main"
Sheets("Squat Main").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
        
Case "Squat Assist"
Sheets("Squat Assist").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
           
Case "Squat Supp"
Sheets("Squat Supp").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
              
Case "Prime DL"
Sheets("Prime DL").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
   
Case "DL Assist"
Sheets("DL Assist").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value
      
Case "DL Supp"
Sheets("DL Supp").Cells(3, Columns.Count).End(xlToLeft).Offset(, 1).Resize(19).Value = Sheets("Calculator").Range("R1:R19").Value

End Select

End Sub