The skylight of the Oculus, with tape holding pieces in place, on September 7, 2019.

The skylight of the Oculus, the sculpture that tops the $4 billion World Trade Center Transportation Hub, has a leaking problem. And while the Port Authority has previously said it hoped to have the issue fixed by the time of the upcoming anniversary of the 9/11 attacks, it looks like that won’t be the case.

In a Thursday press release, the Port Authority said that the skylight—made up of 224 panes of glass and arranged on 40 motor-powered panels for opening and closing—will not open this year on September 11.

“Under the advice of expert consultants, we are conducting engineering analysis on the Oculus skylight operating systems and reviewing carefully the best approach to repair a complex, one-of-a-kind architectural feature,” a Port Authority spokesperson told Curbed in a statement. “Our priority is to get it right.”

The skylight was designed to open and close each year on the anniversary of the attacks, letting a beam of light into the space at precisely 10:28 a.m., the moment the North Tower of the World Trade Center collapsed.

The Oculus on September 7, 2019, with tape on the exterior skylight.

Last year, during the 9/11 remembrance events, a rubber seal may have ripped from the skylight during its opening and closing. Since then, the Port Authority has reportedly spent more than $30,000 trying to patch it up with waterproof tape. Still, the structure leaked again on May 5.

Designed by Spanish starchitect Santiago Calatrava, the $3.9 billion World Trade Center Oculus opened in March 3, 2016.

Though the skylight won’t be part of the remembrance events this year, the Port Authority will hold an interfaith service at St. Peter’s Church on Wednesday, September 11 at 2 p.m. honoring the lives of 84 employees lost during the 9/11 attacks, as well as the victims of the 1993 World Trade Center bombing. The agency will also fly a flag at the George Washington Bridge from 7:15 a.m. to 1:15 p.m. Prior to the Port Authority service, the 9/11 Memorial and Museum will host the annual commemoration ceremony, which begins around 8:30 a.m.