It happens that an airline supports several loyalty programs. However, at the time of booking, the airline requires that only exactly one card number is submitted. It is not possible to submit multiple loyalty cards at the same time.
Therefore, if there are several loyalty programs to choose from for one of your bookings and you have several card numbers stored in your user account, the airline will select the first card that it recognizes as eligible in the list of card numbers submitted by us during the booking process.
You are a member of the Lufthansa Miles & More program and at the same time a member of the Eurowings Boomerang Club and have also stored both card numbers in your user account.
Now you book a Eurowings flight.
We submit all your stored card numbers. However, we unfortunately have no influence on which of the two cards is taken into account in the booking.