There's a glitch when adding numerals to a line CSV (VB.NET) - vb.net

Question

All of the number 6's in column 6 (Item(5)) should be deleted, and the rest of the numbers should be increased by 1. However, when the process is completed, I check the file and the file is unchanged.
Dim liness As New List(Of String)(File.ReadAllLines("F:\Computing\Spelling Bee\stdnt&staffdtls.csv"))
For Each line As String In liness
Dim item() As String = line.Split(","c)
Do
If item(5) = 6 Then
liness.Remove(line)
Else : Exit Do
End If
Exit Do
Loop
Console.WriteLine("Have you already entered the next school years, year 3's? (y/n)")
Dim year3s As String = Console.ReadLine
If year3s = "Y" Or year3s = "y" Then
For i As Integer = 1 To liness.Count - 1 'this will read to the end of the array list once
If item(5) > 3 And item(5) < 6 Then
item(5) = item(5) + 1
End If
Next
ElseIf year3s = "N" Or year3s = "n" Then
For i As Integer = 1 To liness.Count - 1 'this will read to the end of the array list once
If item(5) > 2 And item(5) < 6 Then
item(5) = item(5) + 1
End If
Next
End If
File.WriteAllLines("F:\Computing\Spelling Bee\stdnt&staffdtls.csv", liness)
Exit For
Next
Exit Do
ElseIf enter.Key = ConsoleKey.End Then
Console.Clear()
adminmenu()
End If

Answer 1

You are updating the 'item' array, but not the 'liness' list. When you write the new 'liness' list to the file, any changes you made to the 'item' array are ignored.
Also, you are writing the 'liness' list back to the file for every loop iteration - this has to be wrong - you probably want to do that after the loop.

Answer 2

While I don't condone using the Split() function for parsing CSV data, I'll leave that part alone here in order to highlight other improvements in the code:
Dim minYear As Integer = 2
Console.WriteLine("Have you already entered the next school years, year 3's? (y/n)")
If Console.ReadLine().ToUpper().Trim() = "Y" Then minYear = 3
Dim NewLines = File.ReadLines("F:\Computing\Spelling Bee\stdnt&staffdtls.csv").
Select(Function(l) l.Split(","c) ).
Where(Function(l) Integer.Parse(l(5)) <> 6 ).
Select(Function(l)
Dim x As Integer = Integer.Parse(l(5))
If x >= minYear Then x += 1
l(5) = x.ToString()
Return String.Join(",", l)
End Function).ToList()
File.WriteAllLines("F:\Computing\Spelling Bee\stdnt&staffdtls.csv", NewLines)