Sorry, but in this case no. There was no obligation on their part to notify you of anything.
Actually, by the rules you agreed to, you notified the airline the child was not travelling by not using the outbound ticket. Meaning, you changed the ticket, not Lufthansa.
Unfortunately, at this point, all you might be entitled to is a refund or voucher for the unused ticket.
Credit:stackoverflow.com‘
4 Mar, 2024
5 Mar, 2024
4 Mar, 2024