Avoidance of paying claim from Momentum Health

I'd been a member of Momentum Health since August 2014 and never claimed. I was unable to pay my October premium and decided to pay it with the November one as I had done before without hassles from the medical aid and had missed a debit to double it in the next month. In December I was involved in a serious head on collision and needed medical care. The missed premiums were paid and the medical aid informed me that there will not be any issues as the premiums had been paid. The hospital informed me that Momentum was not responding to their claim. The medical aid was contacted again and this time they asked for the December premium to be paid in as well and this was still mid December and that a Re Instatement form must be completed as they had cancelled my membership without my knowledge. All of this was done, when contacted again they said the Re Instatement was not approved and they would not pay for the account as it was a lot of money and they were afraid I would leave them after the payout. They gave me the option of giving me back my premiums and reopening a new membership or transfer the premiums into the new account but still not pay. Very disappointing service.