Double-Billing Complaint Since July '22

I have never been so frustrated by a company's customer care and billing system as with PathCare. I sent the complaint below in August 2022 with follow-up emails since then and have received no response. However, I am getting endless emails and SMSes about a bill I owe when I have not received any response to my query. Please can I get a response because the Client and Accounts email address are clearly not yielding any results.

"Dear PathCare,

I hope that this email finds you well.

I would like to register a complaint and grievance which I hope will be resolved soon.

I have been double billed for test results which I have already received and paid for. I received the first statement at the end of last month (July) which I had paid for and reflected on your systems. A day later, I received the second bill which does not make sense as the results in question had already been received and paid for in the first statement.

I have been calling your offices since I received the second bill to resolve this matter however, this has been a frustrating process. The accounts agents keep stating that they send statements on results received however the second bill is re-charging me on results that are reflected and paid for on the first bill.

In August, the nurse practitioner at my local clinic who received the results on my behalf called your offices and stated that she did not request any additional tests. We had checked the documentation of results and the first bill reflects what was received hence our collective shock on receiving the second bill.

In August, I sent a Facebook message on this matter. A day later, I received a call from the Senior Laboratory Technician stating that she would get back to me on how it came that I had received another bill. She has not gotten back to me and I am still awaiting her response.

Now, last night, I received a letter of demand from your offices which I find highly frustrating and problematic considering my efforts in trying to resolve this matter. I would like for this matter to be speedily resolved as this has been ongoing for close to a month.

I look forward to your swift response."