Problems with the match function in Excel

excel| Function | problem
Sub Usematch ()
Dim s_p As String, e_p as String
Dim Num as Integer
num = 0
For each M in Range ("A:a")
If m.value <> "" Then
num = num + 1
Else
Exit for
End If
Next M
Erange = "B" & Num
Erange = "B2:" & Erange
N = 1
A = 2
Currange = "B" & A
Cells.select
Selection.sort Key1:=range ("A2"), Order1:=xlascending, Key2:=range ("B2") _
, Order2:=xlascending, Header:=xlguess, Ordercustom:=1, matchcase:= _
False, Orientation:=xltoptobottom, Sortmethod:=xlpinyin, dataoption1:= _
Xlsortnormal, Dataoption2:=xlsortnormal
Columns ("A:a"). Select
Selection.insert Shift:=xltoright ' left insert one column
Set Curcell = Worksheets (Sheets (1). Name). Range (Currange)
For all M in Range (Erange)
On Error GoTo ErrorHandler
If m.offset (0,-1). Value <> "" Then GoTo Mynext
If m.offset (0, 1). Value = "" Then GoTo mynext ' current cell left empty/Right cell content is empty
s_p = m.value:e_p = M.offset (0, 1). Value

pos = Application.WorksheetFunction.Match (e_p, Worksheets (1). Range (Erange), 0) ' Find the number of rows that appear in the Start column for the end point
If pos = "" Then
Curcell.offset (0,-1). Value = "NO"
GoTo Mynext ' If not found then set to ' no '
End If
Thenext:
Position = "B" & Trim (STR (POS)) ' navigates to the cell
If Range (Position). Offset (0, 1). Value = s_p Then
If Range (Position). Offset (0,-1) = "Then ' if satisfied, mark before corresponding record
Curcell.offset (0,-1). Value = N & ". A
Range (Position). Offset (0,-1). Value = N & ". B
n = n + 1
Else
Curcell.offset (0,-1). Value = "NO"
End If

Else
If Range (Position). Offset (1, 0). Value = E_p Then
pos = pos + 1
GoTo Thenext
Else
Curcell.offset (0,-1). Value = "NO"
End If
End If
MyVar = 0

Mynext:
A = a + 1
Currange = "B" & A
Set Curcell = Worksheets (Sheets (1). Name). Range (Currange)
Next
ErrorHandler:
Curcell.offset (0,-1). Value = "NO"
Resume Next
End Sub

The form is: column A and column B. The matching criterion is: query by row, and if the first row of column a cell contents equals another row of column B cell contents, check that the contents of column B cells in the first row are equal to the contents of another row of column A, if the equality is marked in front of the two rows. otherwise labeled No