Verifying status of a long list of patients in a spreadsheet. Can't figure out how to mark a cell after verifying text exists on each page.

[JordanStach]

The code cycles through a huge list of patients and plugs their IDnumber and DoB into a portion of a URL, then opens a webpage to check that they're marked as eligible for some service. That all works fine, but I'm having trouble automating the marking of cells to indicate whether a patient is eligible.

I'm very new (day 4) to this, and I don't have any background in coding, so I'm sort of stuck at sea at this point. Not sure which direction to start moving...

This is a snapshot of the HTML I'm trying to target:

https://imgur.com/SgOe9zY

And this is the code (removed the actual URL for privacy):

Sub SomeModule()


    FinalRow = Cells(Rows.Count, 1).End(xlUp).Row
    For i = 2 To FinalRow

        Dim IE As New InternetExplorer
        IE.Visible = True
        IE.Silent = True
        
        IE.navigate "https://website.com/" _
            & Range("A" & i).Value _
            & "&dob=" _
            & Range("C" & i).Value
            
        Do
        DoEvents
        Loop Until IE.readyState = READYSTATE_COMPLETE
        
        Dim Doc As HTMLDocument
        Set Doc = IE.document
        
        If InStr(IE.document.getElementsByClassName("alert alert-success big").innerHTML, "patient is eligible") > 0 Then
        
            Range("F" & i) = "Elligible"
        
        End If
        IE.Quit: Set IE = Nothing

    Next i



End Sub

I get an error on the 'If InStr' line. "Runtime Error 438: Object doesn't support this property or method."

Any advice is appreciated.

 

[JordanStach]

    Sub SomeModule()
    
    
        FinalRow = Cells(Rows.Count, 1).End(xlUp).Row
        For i = 2 To FinalRow
    
            Dim IE As New InternetExplorer
            IE.Visible = True
            IE.Silent = True
            Dim codeLine As String
            Dim startPos As Long
            
            IE.navigate "https://website.com/" _
                & Range("A" & i).Value _
                & "&dob=" _
                & Range("C" & i).Value
                
            Do
            DoEvents
            Loop Until IE.readyState = READYSTATE_COMPLETE
            
            Dim Doc As HTMLDocument
            Set Doc = IE.document
            
            Dim HTML As HTMLDocument
            
            
            mes = IE.document.body.innerHTML
    
            startPos = InStr(mes, "patient is eligible")
            If startPos = 0 Then
                ActiveSheet.Range("F" & i).Value = "Not eligible."
            Else
                codeLine = Mid(mes, startPos, InStr(startPos, mes, ";") - startPos)
                ActiveSheet.Range("F" & i).Value = "Patient is eligible."
            End If
    
    
            IE.Quit: Set IE = Nothing
        Next i
    
    
    
    End Sub

Solved.