Selena Gomez set out to create “the world’s first mental fitness ecosystem.” Instead, the startup is becoming her own personal headache.

A federal lawsuit filed Thursday offers a detailed account of what investors say went wrong at Wondermind — from an app that was never built to major corporate partnerships they allege never existed.

Gomez launched the startup in 2021 alongside her mother, Mandy Teefey, and Daniella Pierson, a business partner. The lawsuit accuses Gomez, her cofounders, and Wondermind of defrauding investors, among other claims.

The investors include Brent Saunders, the CEO of Bausch + Lomb and former CEO of Allergan, and…