Taylor Swift accused her former record label of blocking her from performing her old songs at an awards show or using them in an upcoming documentary, escalating a dispute between the pop star and powerful celebrity manager Scooter Braun.

The singer-songwriter tweeted an impassioned plea asking U.S. asset management firm Carlyle Group and fans to help her in efforts to secure ownership of six albums she previously recorded under Big Machine Label Group LLC.

In the tweet, the singer called out Braun and Big Machine record label founder Scott Borchetta for “exercising tyrannical control” by declining to let her use her older music or performance footage in an upcoming American Music Awards show and Netflix documentary.

“I feel very strongly that sharing what is happening to me could change the awareness level for other artists and potentially help them avoid a similar fate,” Swift said in the tweet.

Braun bought the label, Big Machine, earlier this year, a deal Swift has publicly opposed. She has threatened to rerecord her songs unless Braun and Big Machine sell her music back to her, and claimed that Big Machine would only let her use her music if she promised not to do so. A representative for Braun didn’t immediately respond to a request for comment.

Borchetta previously said in a blog post that he’d offered Swift control of her music in exchange for a 10-year record deal, but she walked away to join Universal Music Group Inc.

Swift recorded the biggest hits of her career for Big Machine, including “Shake It Off,” “We Are Never Ever Getting Back Together” and “Look What You Made Me Do.” Swift just released “Lover,” her first album since signing a new deal with Republic Records, a division of Universal Music Group. Universal also distributes music from Big Machine.