Be Polite and Patient: While it's understandable to feel frustrated, it's important to remain polite and patient when dealing with airline staff. They are more likely to assist you if you approach them calmly and respectfully.
Check for Additional Costs: Depending on the reason for missing your flight, there may be additional costs involved in rebooking or changing your travel plans. Ask United Airlines Missed Flight about any fees or charges associated with rebooking.