VBA Code - Create Log sheet (Errorlog) in case VBA Macro condition is not met

Option Explicit
Dim ErrorLogRow As Long
Dim wsErrLog As Worksheet

Sub COMBINE()

Dim i As Long, existWS As Boolean
' Add Sheet ErrorLog if not Exists
Dim wsCurrent As Worksheet: Set wsCurrent = ActiveSheet ' Save active sheet name
For i = 1 To Worksheets.Count 
    If Worksheets(i).Name = "ErrorLog" Then
        existWS = True
        Set wsErrLog = Worksheets("ErrorLog")
    End If
Next i
If Not existWS Then
    ActiveWorkbook.Sheets.Add(After:=ActiveWorkbook.Sheets(ActiveWorkbook.Sheets.Count)).Name = "ErrorLog"
    Set wsErrLog = Worksheets("ErrorLog")
End If
wsCurrent.Select ' Return to active sheet

ErrorLogRow = wsErrLog.Range("A" & wsErrLog.Cells(Rows.Count, "A").End(xlUp).Row).Row ' Row to write Error Log

Call GSTR1
Call GSTR2
Call GSTR3
Call GSTR4


Application.ScreenUpdating = False

' Display a message when the task is completed
Application.ScreenUpdating = True: ErrorLogRow = 0
MsgBox "Validation done successfully!", vbInformation

End Sub

Sub GSTR1()

Dim lastRow As Long
Dim i As Long

lastRow = Cells(Rows.Count, 9).End(xlUp).Row ' Assuming data starts from row 1

For i = 9 To lastRow
If Not IsEmpty(Range("A" & i).Value) And IsEmpty(Range("BL" & i).Value) Then
ErrorLogRow = ErrorLogRow + 1: wsErrLog.Range("A" & ErrorLogRow).Value = "Blank cell in column BL at cell BL" & i & ""
End If
Next i

End Sub

Sub GSTR2()

Dim lastRow As Long
Dim i As Long

lastRow = Cells(Rows.Count, 9).End(xlUp).Row ' Assuming data starts from row 1

For i = 9 To lastRow
If (Range("C" & i).Value = "EXWOP" Or Range("C" & i).Value = "EXWP") And Range("AJ" & i).Value = "G" Then
If IsEmpty(Range("AC" & i).Value) Or IsEmpty(Range("AD" & i).Value) Or IsEmpty(Range("AE" & i).Value) Then
ErrorLogRow = ErrorLogRow + 1: wsErrLog.Range("A" & ErrorLogRow).Value = "Blank cell(s) in columns AC, AD, or AE at row " & i & ""
End If
End If
Next i
End Sub

Sub GSTR3()

Dim lastRow As Long
Dim i As Long

lastRow = Cells(Rows.Count, 9).End(xlUp).Row ' Assuming data starts from row 1

For i = 9 To lastRow
If Not IsEmpty(Range("A" & i).Value) And IsEmpty(Range("BB" & i).Value) Then
ErrorLogRow = ErrorLogRow + 1: wsErrLog.Range("A" & ErrorLogRow).Value = "Blank cell in column BB at cell BB" & i & ""
End If
Next i

End Sub

Sub GSTR4()

Dim lastRow As Long
Dim i As Long

lastRow = Cells(Rows.Count, 9).End(xlUp).Row ' Assuming data starts from row 1

For i = 9 To lastRow
If Not IsEmpty(Range("A" & i).Value) And IsEmpty(Range("AY" & i).Value) Then
ErrorLogRow = ErrorLogRow + 1: wsErrLog.Range("A" & ErrorLogRow).Value = "Blank cell in column AY at cell AY" & i & ""
End If
Next i

End Sub