If you are running late, the first step is to check in online or via the airline's app immediately; this can save you from being "bumped" if the flight is overbooked. If you have already checked in but haven't reached the gate, call the airline while en route or use their app's "rebook" feature. Once at the terminal, skip the check-in kiosks and head straight to a "priority" or "customer service" desk to explain your situation. If you are at security and your flight is boarding, politely ask a TSA/Security officer or other passengers if you can move to the front; most people are empathetic to a time crunch. If you miss the gate closing (usually 15–20 minutes before departure), the "Flat Tire Rule" may apply—this is an informal airline policy where agents may rebook you on the next available flight for free or a small fee if you arrive within 2 hours of your original departure. Always stay calm and kind, as agents are far more likely to help a polite passenger than an angry one.