Yellow sweat stains ruining your mattress? Fans of cleaning guru Mrs Hinch swear by a £2.50 spray that works ‘miracles’ by lifting the most stubborn marks and smells ‘amazing’Yellow sweat stains ruining your mattress? Fans of cleaning guru Mrs Hinch swear by a £2.50 spray that works ‘miracles’ by lifting the most stubborn marks and smells ‘amazing’