Nightingale Properties is reportedly trying to change its plans to buy the famed Coca-Cola building on Fifth Avenue.

The company — which had struck a deal to buy the property at 711 Fifth Ave. for more than $900M, with Ashkenazy Acquisition Corp. and Wafra as joint venture partners in May — has filed a lawsuit in Manhattan State Supreme Court claiming Coca-Cola is in breach of their agreement, The Real Deal reports.

Nightingale is arguing that Coca-Cola didn't reveal a letter from back in 2017 between the company and the Swatch Group, which owns Swiss watchmaker Breguet, a ground-floor retail tenant, per TRD.

Nightingale planned to convince Swatch to buy out the remainder of its lease in the building, which could be a windfall if it can sign a new tenant at increased rent. Nightingale claimed in court the letter could changes its outlook for the deal, therefore Coca-Cola should have previously disclosed it, The Real Deal reported. There are questions, however, as to whether or not Nightingale has the capital for the deal, which would be one of the largest in the company's history.

Coca-Cola announced its plans to sell the building late last year. The soft drink giant has owned it since 1983, when it picked it up as part of its acquisition of Columbia Pictures.

The building, which is at the corner of East 55th Street, spans 354K SF and is mainly used for office and retail space. In 2017, Ralph Lauren shut its store there amid declining sales. Cushman & Wakfield’s Doug Harmon and Adam Spies are marketing the building.