Storage issue with linked list VB.NET - vb.net

Question

i am using vb.net to create a linked list, and am finding an issue with storage. the second to last value entered is always deleted. i believe this issue is in the Add() subroutine, but i cant figure out how this is caused, or how to fix it. attached is the code and ss of the console. console output
Module Program
Structure linkedList
Dim item As String
Dim position As Integer
Dim pointer As Decimal
Dim isEmpty As Boolean
End Structure
Dim tail As Integer
Dim input As String
Dim list(30) As linkedList
Dim index As Integer
Const head As Integer = 0
Dim menuChoice As Integer
Sub Main()
For i = 0 To list.Length - 1 : list(i).isEmpty = True : Next
menu()
End Sub
Sub menu()
Do
Try
Console.WriteLine("Press 1 to add values, 2 to remove them.")
menuChoice = Console.ReadLine
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
Loop Until menuChoice = 1 Or menuChoice = 2
Select Case menuChoice
Case 1
add()
Case 2
remove()
End Select
End Sub
Sub add()
list(0).position = -1
list(0).item = "Head"
index = 1
Do
Console.WriteLine("Enter a value to enter into the linked list, or press X to stop: ")
input = Console.ReadLine
If input <> "X" And input <> vbNullString Then
For i = 0 To list.Length - 1
If list(i).isEmpty = True Then
list(i + 1).item = input
list(i + 1).position = index
list(i + 1).pointer = index + 1
list(i).isEmpty = False
Exit For
End If
Next
End If
list(0).pointer = findNextAvailable(0)
If input <> "X" Then : index += 1 : End If
If input = "X" Then
tail = index
End If
Loop Until input = "X" Or index = 30
showList()
End Sub
Sub remove()
Dim checked As Boolean = False
Dim removString As String
Dim removPos As Integer
Dim removPoint As Integer
Dim num1 As Integer
Do
Try
Console.WriteLine("Enter a string to remove from the Linked List:")
removString = Console.ReadLine.Trim
For i = 0 To list.Length - 1
If list(i).item = removString Then
checked = True
removPos = i
num1 = i - 1
list(i).isEmpty = True
Exit For
Else
checked = False
list(i).isEmpty = False
End If
Next
Catch ex As Exception
Console.WriteLine(ex.Message)
End Try
Loop Until checked = True
list(removPos).item = vbNullString
list(removPos).pointer = fixPointer(num1)
list(num1).pointer = findPos(removPos)
showList()
End Sub
Function findPos(start As Integer) As Integer
Dim check As Boolean
Dim num1 As Integer
For i = start To list.Length - 1
If list(i).item <> vbNullString Then
check = True
num1 = i - 1
Exit For
End If
Next
If check = True Then
Return num1
Else
Return vbNullString
End If
End Function
Function findNextAvailable(startPoint As Integer) As Integer
Dim nextAvailableTrue As Boolean
Dim num1 As Integer
For i = startPoint To 0 Step -1
If list(i).item <> vbNullString Then
nextAvailableTrue = True
num1 = i
Exit For
End If
Next
If nextAvailableTrue Then
Return num1 + 1
Else
Return startPoint + 1
End If
End Function
Function fixPointer(r As Integer) As Integer
Dim i As Integer = 0
Dim check As Boolean = False
Do
If list(i).item <> vbNullString Then
check = True
End If
i += 1
Loop Until check = True
For x = 0 To list.Length - 1
If list(x).pointer <> vbNull And list(x).item = vbNullString Then
list(x).pointer = vbNull
End If
Next
list(r).pointer = list(i).position
Return list(r).pointer
End Function
Sub showList()
Dim lastPosition As Integer = 0
For x = 0 To list.Length - 1
If list(x).isEmpty Then
list(x).pointer = 0
list(x).position = x
End If
If list(x).isEmpty = False Then
lastPosition = list(x).position
End If
Next
list(lastPosition).item = vbNullString
list(lastPosition).pointer = 0.0
For i = 0 To list.Length - 1
Console.WriteLine($"{list(i).position} ¦ {list(i).item} ¦ {list(i).pointer}")
Next
Console.ReadLine()
menu()
End Sub
End Module