Condé Nast’s experience since moving into Manhattan’s One World Trade Center has not been as graceful as its glossy magazines, and the company is threatening to sue the tower’s developers over filthy, broken windows.

Most of the office building’s windows have not been cleaned since the media company moved into the tallest building in the U.S. in 2014, according to a notice of claim it filed against the Port Authority of New York & New Jersey and the Durst Organization, the tower’s owners. Beyond the filth, the windows are cracked and in need of repair, the New York Post reports.

The company has repeatedly reached out to the development team to fix the problem, but the developers have done nothing, Condé Nast attorney Marc Kasowitz told the Post.

“Most of the windows in Condé Nast’s space are dirty and not transparent, preventing its employees from being able to enjoy their space in the manner consistent with high rents outlaid by Condé Nast,” the claim reads.

The company originally signed a $1.9B, 25-year lease for nearly 1.2M SF on floors 20 through 44 and has paid $1.2M in glass-cleaning fees over the last two years. The notice of claim, normally a preface to a lawsuit, seeks a refund for the window-cleaning fee.

This is not the first complaint Condé Nast has had with its downtown office since moving from 4 Times Square in midtown Manhattan. A rat infestation in the Vogue offices on floors 25 and 26 had editor-in-chief Anna Wintour refusing to work from her office until the building was rat-free. Wintour previously complained about the building’s lack of proximity to a Starbucks in her February 2015 editor’s letter. One has since opened across the street at the Oculus mall.