Steel, 11, caused controversy during last year's series of the competition when she broke down during her performance of 'Edelweiss'.
Her mother Nina has now told the Daily Star that the acts' management company "dropped [her] like a penny" when the show ended.
"As soon as the show has finished you don't hear a word from them ever again," she said. "The 2008 finalists - including Faryl Smith, who's a similar artist to Hollie - did very, very well from it. They got record deals and things like that. Hollie didn't get anything. We believed Hollie's talent was good enough to get some sort of recognition but nobody came forward."
Three businessman agreed to invest in Steel following an online campaign in January and Nina Steel has now decided to take six months off work to support her daughter as she promotes her debut album Hollie.
"I feel let down because I think Hollie has a really beautiful talent," she added. "I'm a mum and now I'm a bloody record producer and manager. It's ridiculous."
The new series of Britain's Got Talent begins on April 17.
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