The 18-year-old musician, whose real name is Jay Bradley, announced the news on his Instagram story on Tuesday (June 19).
“@blacchyna and I are no longer together,” he wrote on the post which he later deleted.
Their breakup comes after he proposed to Chyna on social media.
“Will you marry me?” he asked with a ring emoji in April.
It’s unclear if she accepted the public proposal.
Chyna, 30, and Bradley first got together in February after she briefly dated Mechie. Both relationships followed her engagement to Rob Kardashian, with whom she shares a daughter named Dream.
She also shares 5½-year-old son King Cairo with ex-fiancé Tyga.
Bradley is best known for his 2017 hit “Chopsticks” and was recently featured on a track by Rich the Kid called “Beware.”