Poor treatment of a very loyal supporter

We joined Bonitas in 2022. In 2024 we had to buy a new car and had to make the tough decision to cancel our membership and we cancelled 1.6.2024. We were planning to rejoin once we paid off the car. I was very happy with the service and I weekly suggest the medical aid to people asking on social media. In 2025 we suddenly got contacted by collections agencies who said that Bonitas handed us over for outstanding monies. When I queried this with Bonitas, they said we never paid our first payment of April 2022. We did not claim in April and we were never told that we had to pay in advance and pay twice in April when we joined. We never had arrears stated on our monthly statements.

Despite this and despite the fact that this is more than 3 years later, I am being constantly harassed by different collections agencies. I am not legally responsible for this payment but Bonitas is refusing to stop this harassment.