Really bad service

I am in general happy with DHMS. On 31 October 2019 I contacted them to reinstate my premium, transfer the premium to private status and downgrade the plan to a bit more affordable price ( since I left my previous employer who paid the premium and I did not need all that benefits anymore). They rep**** to me on 1 November 2019 to just fill in the necessary documents to do the reinstatement, transfer to private status and do a plan change. I did it and they went on to only reinstate, and transfer to private status. It was a struggle to communicate with them and for three months after that I had to pay the more expensive premium. So they disregarded my request at my own expense. Finally in March I will pay the lower premium.