New house - Ring siren mounted before QR code was scanned - do I now have to get on a ladder to setup?

Hi all,

As per title, can someone advise what I can do here? Essentially I’m building a house and the builders have already mounted the (hard-wired) Siren so it’s v.difficult to access. Do I need the QR code to set it up? Or is there another way to pair a pre-mounted siren?

theres also a copy of the qr code on the bottom of the box it came in.