KENNEDY SPACE CENTER, Fla. - An active investigation into a leak repair on the International Space Station continues to cause NASA to shift the launch of four private astronauts on the Axiom Space Mission 4. The Axiom Mission 4 crew was set to launch on a SpaceX Falcon 9 and Dragon spacecraft last week from NASA's Kennedy Space Center in Florida, but a leak with SpaceX's rocket at the space station has delayed the private mission. Then the mission faced an additional delay after NASA said it needed more time for an ongoing investigation to understand a "new pressure signature, after the recent post-repair effort" on the space station’s Zvezda service module. Roscosmos cosmonauts recently completed repair work on the service module to stop the leak, which has been monitored by flight controllers for a few years. NASA said after the repairs, the pressure remained stable in the transfer tunnel and the hatch seal between the ISS and the back of the Zvezda module. Previously, the pressure would have dropped in this area, indicating the small leaks may be fixed, according to NASA.