Telephonic harassment

I was a member of discovery medical aid since 2016. This year March I discontinued my membership as I was changing jobs. At that time I had already used some funds from the medical aid without knowing that i will end up owing them. During the month of April, when I had just started my new job I received a call from discovery, a lady by the name Duduzile. She explained that I owe the scheme and she explained how I got to owe that money. So I told her that I can only start making payment on 2June as I didn’t know what my nett salary will be on the new job. She then promised to send me the details so that I can make the payment on 2 June. I waited and nothing came through. On Wednesday (6June at 09:43) I received an email from discovery with the banking details...so late already. Since I no longer had the money I decided that i will start making 2July. A few minutes ago I received a call from discovery, harassing me, telling me that I’m lying I got the email long ago and I just decided to sit and not make the payment. I tried to explain that I only received the email recently but the more I tried to explain, the bitter the harassment became. So I put the phone down and discovery immediately sent another email similar to the one I received last Wednesday. So much abuse from discovery health...yoh