The company syas I owe them but will not tell me the details

Last year, in the beginning of the year I was a patient in Wilgeheuwel Hospital. According to our medical aid records and our personal records, all our bills were paid for. A year later I started to receive phone calls, emails, and sms's from a company called ITC stating we owe money to Wigeheuwel Hospital. I requested each time I spoke to a representative who called me to send me the details so that I can sort it out. Nothing has been sent, and we have given them three email addresses. I do not even know the amount they say is owing, as none of the messages ever tells me this, and neither do the representatives. I rep**** to their email with this request, which I copied my lawyer in (after two months of these messages) requesting the information. (My email tracker says that it was opened and read). Still no information. I tried to contact Wilgeheuwel accounts department, was referred to Life Healthcare accounts department, where I was told to speak to a specific person. She is never available. I have left messages with no returns calls. I am at wits end with this and I am still battling to get it sorted out. My next step is to get my lawyer directly involved, but that will probably cost more than I owe, if I do owe anything.