Copy rows into sheet according to entries in Column

Hi thanks for you replies. The code works fine on its own when the sheets are created but when I try to attach it to a user form that I use to open, format and save the spread sheet it does not work.

Error message :- run time error 9 : subscript out of range.

It only seems to work when I save, close and then re-open and run the code separately. When the code is run, the dates change to mm/dd/yyyy, but even when I go to format cell it stays as it is.

Private Sub cbReport_Click()
Private Sub cbReport_Click()
    Dim day As String
    Dim month As String
    Dim year As String
    Dim month_name As String
    Dim year_long As String
    Dim storage_path As String
    Dim generic_file_name As String
    Dim file_name As String
    Dim report_length As Integer
    Dim line_number As Integer
    
    'Assign text box values to respective variables
    day = tbDay
    month = tbMonth
    year = tbYear
    
    'Close Report window and set text box values to null
    Report.Hide
    tbDay = ""
    tbMonth = ""
    tbYear = ""
        
    'Set path for report storage area
    storage_path = Range("Path!A1")
    'Determine generic file name
    generic_file_name = Range("Path!A2")
      
    'Determine report file name from day, month and year
    'Determine month name
    Select Case month
        Case "01"
            month_name = "January"
        Case "02"
            month_name = "February"
        Case "03"
            month_name = "March"
        Case "04"
            month_name = "April"
        Case "05"
            month_name = "May"
        Case "06"
            month_name = "June"
        Case "07"
            month_name = "July"
        Case "08"
            month_name = "August"
        Case "09"
            month_name = "September"
        Case "10"
            month_name = "October"
        Case "11"
            month_name = "November"
        Case "12"
            month_name = "December"
    End Select
    
    'Determine year in 4 digit format
    year_long = "20" & year & ""

    'Store file name in variable file_name
    file_name = "" & generic_file_name & " " & day & " " & month & " " & year & ".xls"
       
    'Open report file
    Workbooks.Open Filename:="" & storage_path & "\" & year_long & "\" & month_name & "\" & file_name & ""
            
    'Procedure to format report with:
    
    Call AddsheetstoPrint
    
    Call x
       
exit_point:
    'Save report file
    ActiveWorkbook.Save
    'Close report file
    ActiveWorkbook.Close
    'Return to Main worksheet on macro program file
    Sheets("Main").Select
    'Display confirmation message box
    MsgBox "Report completed, stored in file:" & Chr(13) & storage_path & "\" & year_long & "\" & month_name & "\" & file_name & "", , ""
End Sub
    
End Sub

The Call Addsheets to print formats the sheets for printing and Call x copies the rows into the corresponding sheets.