U.S. based Delta airlines has reportedly cancelled around 800 flights of its mainline operations. The cancellations come after the airline operations were halted due to a global cyber outage that impacted airlines around the globe.

The Atlanta-based airlines is facing an ongoing operational problem caused by the impact of the outage on its crew tracking system.

The ongoing problem has resulted in thousands of passengers filing complaints and having to resort to renting cars to drive hundreds of miles and others facing days of delays or cancelling trips altogether.

While the airline has not offered any timeline on when flight operations would resume, it has reportedly offered flight attendants extra pay to pick up shifts, CNBC reported.

On Monday, Microsoft released a custom tool to its users to rectify the damage caused by a CrowdStrike software update.