Held liable for service not used- Please cancel

I have registered with Oxbridge Academy in 2013 to study a HR diploma, I paid the registration fee and the first 3 installments. I received the first batch of text books after the payment. However unfortunately I lost my job and was not able to continue to make the payments. I called them to advise them of my situation and they agreed to place the account on hold.<br> Last year I got ****** of my cellphone so my number had changed , however my residential, postal and email address all remained the same. I have not received any letters or emails from them notifying me that my account will be handed over. Tuesday they sent me an email to say my account has been handed over to the attorneys.They are holding me liable for an amount of R4200. I have not received any text books or handed any assignments in during the period that my account had been on hold. They also advised that they want an immediate minimum payment of R2800 which is really unaffordable.I was not given any prior notice since 2013 that my account will be handed over. They are not able to tell me what is the reason for not sending any letters. Why am I liable for a facility I did not use. <br> I want this account to be cncld