Run-time error 438 in Access

Private Sub SaveAndAddEmployee_Click()
On Error GoTo Err_SaveAndAddEmployee_Click
    Dim strErrMessage As String
    
    strErrMessage = "Could not save employee due to:"
    
    checkEmpNum (Me.EmployeeNumber)
    
    'if employee number doesnt exist, is not 0 or null then save.
    If Me.EmployeeNumber > 0 Then
        If rsEmployeeCheck.EOF Then
            DoCmd.DoMenuItem acFormBar, acRecordsMenu, acSaveRecord, , acMenuVer70
            DoCmd.GoToRecord , , acNewRec
            MsgBox ("Employee successfully saved.")
        Else
            strErrMessage = strErrMessage & vbCrLf & "- Employee number already exists"
            MsgBox strErrMessage, , "Can't Save Employee"
        End If
    Else
        strErrMessage = strErrMessage & vbCrLf & "- Employee number cannot be 0"
        MsgBox strErrMessage, , "Can't Save Employee"
    End If
        
    
Exit_SaveAndAddEmployee_Click:
    Exit Sub
 
Err_SaveAndAddEmployee_Click:
    If Err.Number = 94 Then 'error number for a null emp number.
        strErrMessage = strErrMessage & vbCrLf & "- Must enter an employee number"
        MsgBox strErrMessage, , "Can't Save Employee"
    Else
        MsgBox Err.message, , "Can't Save Employee" <-- highlighted here
    End If
    Resume Exit_SaveAndAddEmployee_Click
    
End Sub