Shocking termination of medical aid.

I have had my medical aid terminated out of the blue, while my husband was still in hospital. I was told i withheld information at the time of application regarding his pre existing condition. He never had a pre existing condition, this is what i have been trying to explain. He was given a clean bill of health by a gp, it was after joining the medical aid did my husband visit a physician who wanted to have him hospitalized to have test run. I am honestly shocked by discovery, who i have always thought so highly of hence my reason for joining them. I never thought of writing a review here but im honestly just so frustrated. Discovery just terminates, and now we stuck with bills to pay that we thought our medical aid would cover.