How to combine multiple excel files (only last 2 months)

I have a macro combine multiple excel files, those files changed every day ( tracker ) and become so big that's impacted my macro and it's become so slow, I try to not get the old information and take only the last 2 month changes, below the code I used with comment. can you please help me it's will be appreciated a lot

Sub CopyFromWorksheets()
    Dim wrk As Workbook 'Workbook object - Always good to work with object variables
    Dim sht As Worksheet 'Object for handling worksheets in loop
    Dim trg As Worksheet 'Combine Worksheet
    Dim rng As Range 'Range object
    Dim colCount As Integer 'Column count in tables in the worksheets
      'We don't want screen updating
      Application.ScreenUpdating = False
    Set wrk = ActiveWorkbook 'Working in active workbook
     
    For Each sht In wrk.Worksheets
        If sht.Name = "Combine" Then
            MsgBox "There is a worksheet called as 'Combine'." & vbCrLf & _
            "Please remove or rename this worksheet since 'Combine' would be" & _
            "the name of the result worksheet of this process.", vbOKOnly + vbExclamation, "Error"
            Exit Sub
        End If
    Next sht
     
  
   
     
     'Add new worksheet as the last worksheet
    Set trg = wrk.Worksheets.Add(After:=wrk.Worksheets(wrk.Worksheets.Count))
     'Rename the new worksheet
    trg.Name = "Combine"
     'Get column headers from the first worksheet
     'Column count first
    Set sht = wrk.Worksheets(2)
    colCount = sht.Cells(1, 255).End(xlToLeft).Column
     'Now retrieve headers, no copy&paste needed
    With trg.Cells(1, 1).Resize(1, colCount)
        .Value = sht.Cells(1, 1).Resize(1, colCount).Value
         'Set font as bold
        .Font.Bold = True
        
    End With
     
     'We can start loop
    For Each sht In wrk.Worksheets
         'If worksheet in loop is the last one, stop execution (it is Combine worksheet)
        If sht.Index = wrk.Worksheets.Count Then
            Exit For
        End If
         'Data range in worksheet - starts from second row as first rows are the header rows in all worksheets
        Set rng = sht.Range(sht.Cells(2, 1), sht.Cells(65536, 1).End(xlUp).Resize(, colCount))
         'Put data into the Combine worksheet
        trg.Cells(65536, 1).End(xlUp).Offset(1).Resize(rng.Rows.Count, rng.Columns.Count).Value = rng.Value
    Next sht
     'Fit the columns in Combine worksheet
    trg.Columns.AutoFit
    
    
     Worksheets("Combine").Activate
     
     Worksheets("Combine").Range("A1").Select
    Worksheets("Combine").Range(Selection, Selection.End(xlToRight)).Select
    Worksheets("Combine").Range(Selection, Selection.End(xlDown)).Select

' ----------solve fusion cells issue --------
 For Each frm In Application.Worksheets
          If frm.Name <> "Dashbord" And frm.Name <> "Combine" Then
             frm.Delete
          End If
       Next frm
Application.DisplayAlerts = True

    For K = 1 To 5
    For i = 3 To Application.WorksheetFunction.CountA(Sheets("Combine").Columns(6))
       If Sheets("Combine").Cells(i, K) = "" Then
        Sheets("Combine").Cells(i, K) = Sheets("Combine").Cells(i - 1, K)
       End If
    
    Next i
Next K

Application.ScreenUpdating = True