Vlookup from other file

Hello all,

I am currently trying to write a VBA-Code, which should use a Vlookup to get specific data from another workbook. (The column from which it should take the data should be flexible based on the month, which is why I implemented "ZielSpalte")
By now, I have the following code:

Public Function LResult(ByVal str As String) As String
      LResult = Mid(str, 11, 7)
End Function

Sub CopyfromInputs()

Dim Month As String
Dim Year As String
Dim ii
Dim ws As Worksheet: Set ws = ActiveSheet

SourceBlatt = "MBR and CF data 2022"
wbkSource = "04MBR-02AA_Ressources_Plants_2022_BaPAA_20220503_1500.xlsx"
wbkUpload = "NWC_Ressources_WebForm_work.v2.xlsm"
UploadRessources = "Ressources_WebForm_BaP"
UploadNWC = "NWC_WebForm_BaP"

Workbooks(wbkUpload).Activate
If Sheets("Identification").Range("C6") < 10 Then Month = "0" & Sheets("Identification").Range("C6") Else Month = Sheets("Identification").Range("C6")
Year = Sheets("Identification").Range("C5")
    

SourceFile = "Link to Sharepoint"


'Open Source File
Workbooks.Open (SourceFile)
Sheets(SourceBlatt).Activate
  
'Define from which column it takes the figures, according to the "Identification" Sheet
Workbooks(wbkUpload).Activate
Sheets("Identification").Activate
IdentificationMonth = Range("C6").Value
ZielSpalte = IdentificationMonth + 3

'Use Vlookup
   Sheets("Ressources_WebForm_BaP").Activate
    lr = ws.Range("A" & ws.Rows.Count).End(xlUp).Row
   
    For i = 7 To lr
                 ii = LResult(Range("A" & i).Text)
                 Cells(i, 4) = Application.WorksheetFunction.VLookup(ii, Workbooks("MBR-02AA_Ressources_Plants_2022_BaPAA_20220503_1500.xlsx").Worksheets("MBR and CF data 2022").Range("A8:T120"), ZielSpalte, False)
    Next i
            
 ActiveSheet.Calculate
 
End Sub

Everything works as it should be (Opening the source file and get lr/ii) until the red line at the end, here VBA is showing the error "Application-defined or object-defined error".
In the original code, I have defined the range of the Vlookup with variables (SourceBlatt/SourceFile), as this was not working I now even used the actual file names, but there still seems to be a problem.

Any hints from your side would be highly appreciated.
Thank you very much in advance!

BR

The file is open, but still does not seem to work. The file is getting opened by "Workbooks.Open (SourceFile) and this part of the code works perfectly fine, just the line with the Vlookup does not seem to work for some reason. You are right with the variable, I will delete it.

Instead of "Link to Sharepont", it is an actual link to the file, I should have made that clear in my comment