Web Data fetch is not updating - excel

Question

I am beginner at VBA. I have done the below code by referring to lot of articles found online.
I am trying to fetch API data from a website. It is taking the first fetch and I need the data to be fetched every 5 mins. But it is not refreshing at all. What can I do? Can anyone have a look at the code and advise?
I am using the below code to get the JSON data and later I am extracting using a JSON parser.
Sub FetchOptionChain()
Dim Json As Object
Dim webURL, webURL2 As String, mainString, subString
Dim i As Integer
Dim j As Integer
Dim k As Integer
Dim l As Integer
Dim dtArr() As String
Dim request, request2 As Object
Dim HTML_Content As Object
Dim requestString As String
webURL2 = "https://www.nseindia.com/"
webURL = "https://www.nseindia.com/api/option-chain-indices?symbol=BANKNIFTY"
subString = "Resource not found"
Set HTML_Content = CreateObject("htmlfile")
'Get the WebPage Content to HTMLFile Object
With CreateObject("msxml2.xmlhttp")
.Open "GET", webURL2, False
.send
End With
FetchAgain:
With CreateObject("msxml2.xmlhttp")
.Open "GET", webURL, False
'Found online that I have to add the below to remove the cached results. Adding this is hanging the excel and it never comes out of it. Excel is hanging here
.setRequestHeader "Content-Type", "application/json"
.setRequestHeader "If-Modified-Since", "Sat, 1 Jan 2000 00:00:00 GMT"
.setRequestHeader "User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36"
.send
mainString = .ResponseText
If InStr(mainString, subString) <> 0 Then
' Data has not been fetched properly. Will wait two seconds and try again.
Application.Wait (Now + TimeValue("0:00:2"))
GoTo FetchAgain

Answer 1

Added end with, end if and end sub. And fixed indenting to make code easier to read.
Sub FetchOptionChain()
Dim Json As Object
Dim webURL, webURL2 As String, mainString, subString
Dim i As Integer
Dim j As Integer
Dim k As Integer
Dim l As Integer
Dim dtArr() As String
Dim request, request2 As Object
Dim HTML_Content As Object
Dim requestString As String
webURL2 = "https://www.nseindia.com/"
webURL = "https://www.nseindia.com/api/option-chain-indices?symbol=BANKNIFTY"
subString = "Resource not found"
'''''''''''''''''''''''''''''''''''''''''''''
''' I don't understand this part though '''
'''''''''''''''''''''''''''''''''''''''''''''
Set HTML_Content = CreateObject("htmlfile")
'Get the WebPage Content to HTMLFile Object
With CreateObject("msxml2.xmlhttp")
.Open "GET", webURL2, False
.send
End With
'''''''''''''''''''''''''''''''''''''''''''''
'''''''''''''''' To here ''''''''''''''''''
'''''''''''''''''''''''''''''''''''''''''''''
FetchAgain:
With CreateObject("msxml2.xmlhttp")
.Open "GET", webURL, False
'Found online that I have to add the below to remove the cached results. Adding this is hanging the excel and it never comes out of it. Excel is hanging here
.setRequestHeader "Content-Type", "application/json"
.setRequestHeader "If-Modified-Since", "Sat, 1 Jan 2000 00:00:00 GMT"
.setRequestHeader "User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36"
.send
mainString = .responseText
End With
If InStr(mainString, subString) <> 0 Then
' Data has not been fetched properly. Will wait two seconds and try again.
Application.Wait (Now + TimeValue("00:00:02"))
GoTo FetchAgain
End If
End Sub
But it runs and works as expected for me.