deposit money

I have had a bad experience with one of the premises that i rented, the landlady has a bad attitude when you enquire over the phone, when i signed the contract it was stated that when you move out you leave a months notice and within 21 days they deposit money into your account, so i served notice to leave in December 2014, and it was supposed to have been deposited in January, i've been enquiry but till today i haven't received anything, i've been sending emails ever since but till today no luck, all i want is my money. Im advising people not to go and rent in their premises they have no service