Originally Posted by PeS

I don't think it was a phishing. Sender is @your.lufthansa-group.com which his valid (although strange it's [email protected] instead of usual [email protected]) and there's no ask to provide any information. All links in the mail lead to standard LH site. Maybe it's simple incorrect wording when they wrote "in advance". But even though, customer relations team answer would still be useless and outright stupid.