The launch of a private astronaut mission to the International Space Station (ISS) has been postponed by NASA as it continues to investigate the ongoing air leaks in collaboration with Roscosmos, the Russian Space Agency.

The Axiom-4 mission launch, the fourth private astronaut mission to the International Space Station, was canceled Tuesday night after SpaceX detected a liquid oxygen leak in its Falcon 9 rocket.

Indian astronaut Shubhanshu Shukla is set to travel to space on board the Axiom-4 mission, making him the country’s second astronaut in space and the first on the International Space Station.