The Home Office have confirmed that an application by the singer's mum Nokuthula Ngazana to extend her working visa has been rejected.
It means that Gamu and her family - who moved to Scotland 8 years ago from Zimbabwe - will now have to leave Britain voluntarily or face deportation.
'The applications made by Ms Ngazana and her family were considered in
line with the published immigration rules,' reads a statement from the
UK Border Agency.
'Ms Ngazana's application was refused as it did not meet all of the conditions for approval.
'Her family, who had applied as her dependants, were therefore also
The Home Office say Nokuthula doesn't have the right to appeal and that Gamu, 18, cannot apply separately to remain in the UK.
Last night, Nokuthula, 38, said she was not aware of the Border Agency's decision.
On Sunday's X Factor, viewers saw Gamu fail to make it into Cheryl Cole's top 3.
The Girls Aloud star instead chose Rebecca Ferguson, Katie Waissel and Cher Lloyd.
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