Sars saying she works in Gauteng nd kzn within few hours apart or same shift

Hellopeter my name is Rethabile writing on behalf of a close friend, problem started in 2015 when she went for submission only to find out that some one is using her personal details and she now owing an amount of R11900 to sars, she's been sent to pilar to pilar without solution she has documentation to prove it and now she's been garnished an amount of R5000 please help