I posted about this previously but not sure how to share it again (new to this - sorry!) but SSC could do nothing to help me so I contacted UEFA and they have said they will be able to sort it following the ticket sales being finalised, just need to explain the issue and give them the order numbers. I contacted them using this link and they emailed me back:
https://support.tickets-euro2024.uefa.com/hc/en-us/requests/new