If your flight reservation shows a "Pending" or "Not Confirmed" status after you have paid, it is usually due to a delay in the ticketing process between the booking platform and the airline. When you book through a third-party site (like Expedia or Booking.com), your payment is processed first, and then the site sends a request to the airline's Global Distribution System (GDS) to issue the actual e-ticket. This "handshake" can take anywhere from a few minutes to 24 hours. Common causes for longer delays include a mismatch in the credit card billing information, a sudden change in the airline's fare price while your transaction was processing, or the flight being "oversold" just as you clicked buy. In 2026, high security filters might also flag a transaction for manual review if it is an international route or a high-value ticket. If you haven't received a 13-digit ticket number via email within two hours, you should contact the booking agency immediately to ensure your seats are secured and the payment has been properly authorized.