Bonitas medical Scheme

I was using Bonitas for a while and after receiving new quotes from different medical schemes i decided to move to a new service provider. after following their procedure of informing them 30 days before termination date via email and filling in their document that they sent me they claimed that they only received the termination document at the end of the termination month. So now i have to pay 2 medical schemes because of negligence on their behalf after i sent them the proof of the emails i have sent out to Bonitas as proof of terminations