Android Question EscPosPrinter QRCode

Public Sub WriteQRCode(size As Int, EC As String, scale As Int, data As String)
    Dim databytes() As Byte = data.GetBytes("ISO-8859-1")
    Dim dhigh As Int = databytes.Length / 256
    Dim dlow As Int = databytes.Length - dhigh*256
    Log("QR Code : Size " & size & ", EC " & EC & ", Scale " & scale & ", Size " & dlow & " " & dhigh & " : Data = " & data)
    Dim params(3) As Byte
    params(0) = scale
    params(1) = dlow
    params(2) = dhigh
    WriteString(ESC & "Z" & Chr(size) & EC.ToUpperCase.CharAt(0))
    WriteBytes(params)
    WriteBytes(databytes)
End Sub

Starter.Crsr = Starter.sqlServer.ExecQuery2("SELECT * FROM EInvoicingIFC WHERE invoice_number=? AND store_id=? AND type=?", Array As String (InvoiceNumber, Main.StoreID,"C"))
            Do While Starter.Crsr.NextRow
                EINVuid = Starter.Crsr.Getstring("uid") ' 7B6F3E378B163C8DEA019047D1E3E7F4E2D0A004
                EINVmark = Starter.Crsr.GetString("mark") '400001928271942
                EINVSignature = Starter.Crsr.GetString("signature") 'EL094196225-1451215-E12E2B05F4F061C5681CD6D549D1A6BA6EACAE41-788CDC5CE91C4657949BE75FE5E36D70
                EINVDomain = Starter.Crsr.GetString("domain") 'https://einvoiceportaluat.impact.gr
                EINVQRcode = Starter.Crsr.GetBlob("qrcode")    'this is varbinary(MAX)
            Loop

            If EINVmark<>"" Then
                Main.Printer.WriteString(Main.Printer.BOLD & "UID: " & EINVuid & Main.Printer.SINGLE & CRLF)
                Main.Printer.WriteString(Main.Printer.BOLD & "Mark: " & EINVmark & Main.Printer.SINGLE & CRLF)
                Main.Printer.WriteString(Main.Printer.BOLD & "Signature: " & EINVSignature & Main.Printer.SINGLE & CRLF)
              
                Dim QRtext As String = EINVDomain & "/v/" & EINVSignature
                Main.Printer.WriteQRCode(512, "M", 3, QRtext)
            Else
                Main.Printer.WriteString(Main.Printer.BOLD & "Entity unable to communicate with the provider" & Main.Printer.SINGLE & CRLF)         
            End If