Estate Agency Failure to pay Rental Deposit

I entered into a one year rental contract( R 7800) with Bianca Properties based on Silver Lakes Road. The contact expired in the 31 December 2017, i moved out of the premises on the 31st December, the property was cleaned, all the keys returned. Paragraph 6.6 of the contract states: 6.2.2 The deposit or the balance thereof will be refunded to the Lessee as soon possible, but no later than 30 days after the termination date. Bianca Properties to date has offered no valid reason as why the deposit has not been paid. The Estate Agency Act requires that the deposit be kept in a Trust.