When a flight is overbooked (a common airline practice), it’s called Denied Boarding. You have clear legal rights, especially in the EU and US
Know Your Rights
The airline must first ask for volunteers. If you are involuntarily bumped, you are entitled to compensation and must be offered an alternative flight.
Key Compensation Tiers
1.US DOT: Compensation depends on the length of the delay to your final destination.
2.EU261: Compensation is fixed, often ranging from €250 to €600, regardless of the ticket price.