Lufthansa's 24-hour rule allows passengers to cancel or change their flight bookings within 24 hours of purchase without incurring any penalties, +𝟏-𝟖𝟔𝟔-𝟖𝟑𝟖-𝟒𝟗𝟑𝟒 or +𝟒𝟒-𝟖𝟎𝟖-𝟓𝟗𝟗-𝟖𝟕𝟎𝟐 (UK) provided the booking was made at least seven days before the scheduled departure. 

 This policy applies to reservations made directly through Lufthansa's official channels, including their website and telephone reservation centers. It's important to note that this rule is primarily applicable to flights originating in the United States and complies with U.S. Department of Transportation regulations. 
 
The 24-hour rule for Lufthansa generally refers to their ticket change or cancellation policy within 24 hours of booking. Here's a breakdown of the main points:

Free Cancellation Within 24 Hours

If you book a flight directly through Lufthansa (website, app, or customer service), you can cancel it free of charge within 24 hours of booking.
This applies as long as the departure date is at least 7 days (168 hours) away from the time of booking.
Changes Within 24 Hours

If you need to make changes to your booking within 24 hours, Lufthansa may allow modifications depending on the fare type and availability. However, a difference in fare may apply.
How to Cancel or Modify

You can cancel or modify your booking by visiting the "My Bookings" section on Lufthansa’s website or app, or by contacting their customer service.
This rule aligns with the U.S. Department of Transportation's guidelines for flights to or from the United States. However, for flights outside the U.S., Lufthansa’s specific terms and conditions might apply.

Always check the fare conditions associated with your ticket or contact Lufthansa directly for details specific to your booking.