Spirit Airlines, the largest budget carrier in the U.S., filed for Chapter 11 bankruptcy protection Monday. The airline said

Since the start of 2020 the airline has lost more than $2.5 billion and has upcoming debt payments in 2025 and 2026 which total more than $1 billion, according to The Associated Press.

The low-fare carrier has struggled to find its footing after its planned merger with JetBlue was blocked by a federal judge.