(ABC 6 News) — Flight attendants at Sun Country, a Minnesota-based airline, are preparing to go on strike.

In fact, 99% of union members voted in favor of going on strike, citing the fact that the airline generated more than $1 billion last year. Meanwhile, flight attendants’ wages have not been adjusted since 2016, meaning they are making less than similar airlines.

Sun Country officials say they are confident they will reach a deal, and the strike will not impact travelers. A mediation session is scheduled for next month.