Is this Mariah Carey's worst lip-syncing fail of all time?

Mariah Carey just suffered a lip-syncing disaster that was anything but a "fantasy". The irony? She was singing her '90s hit 'Fantasy'...

Taking the stage at the 2015 Jazz and Blues Festival in Jamaica, the 44-year-old entered the "hot mess" zone with a string of embarrassing fails.

Poor Mariah messed up lyrics, forgot to sing and tried to salvage it all by pulling passionate singing faces that didn't quite match the mouthing. It just wasn't her day! Watch above.

Fans called out Mariah's lip-syncing when a local review in Jamaica Observer reported that she'd "conquered" the festival.

"She was lipping all night. At one point she had the mic at her mouth the song was playing and the crowd swear she was singing… She didn't do one live song," wrote one fan.

Another concertgoer added that "something about her was not right".

"She kept fixing her hair every five seconds, saying inappropriate things and her 'singing' quality was poor," they wrote. "There were persons [sic] shouting, 'We want the real Mariah!'"

Another YouTube video from the night shows Mariah missing her big note in 'Always Be My Baby'... yikes, it really was an off night.

Mariah faced criticism last year for struggling to reach the high notes on her Elusive Chanteuse world tour. Oh Mimi, we all have bad days...

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