Visual Basic Com Port doesn't Receive - vb.net

Question

I'm Trying to communicate with a com port using a visual basic console application. The com port never receives data, and times out every time. I've confirmed with a different program written in python that the com port and device are working correctly. I am sure that I am just missing something since I am new to VB. I've tried opening the com port using two method, neither of which returned an error (the first method I used is commented out). Below is my script.
Imports System
Imports System.IO.Ports
Imports System.IO
Module Module1
Function ReceiveSerialData(ByVal data As String) As String
' Receive strings from a serial port.
Dim returnStr As String = ""
Dim add As String = "Com6"
'Dim port As New SerialPort("Com6", 9600, Parity.None, 8, StopBits.One)
Dim port As SerialPort = My.Computer.Ports.OpenSerialPort("COM6", 9600, Parity.None, 8, StopBits.One)
Try
Dim state As Boolean = (port.IsOpen)
If state = False Then
Console.Write("Opening Port" + vbNewLine)
port.Open()
End If
port.ReadTimeout = 5000
port.Write("z")
Dim cat As String = port.ReadLine()
Catch ex As TimeoutException
returnStr = "Error: Serial Port read timed out."
Finally
If port IsNot Nothing Then port.Close()
End Try
Console.Write(returnStr)
Return returnStr
End Function
Sub Main()
Console.WriteLine("Enter Command for Telescope!:")
Dim stdin As TextReader = Console.In
Dim sInput As String = stdin.ReadLine
Console.Write("Sending Command " + sInput + "." + vbNewLine)
Dim sent As String
sent = "z"
Dim recv As String
recv = ReceiveSerialData(sent)
Console.Write(recv)
End Sub
End Module