What do I do if long term disability insurance is threatening to discontinue coverage?

I have Multiple Myeloma, bone cancer that has affected my walking, sitting, and standing. Social security has approved my continued disability. I have active disease and according to my doctor, it makes me unable to work full or part time. Insurance states that after an update to my immunizations I should be able to return to the public and thus return to work, overlooking the fact that I have constant pain, unable to stand, walk, or sit for periods, and have consistent neuropathy in my hands and feet. I also take an immunosuppressive drug to control my cancer which makes me susceptible to infections and illness. I also take large amounts of morphine to control pain which affects my ability to stay alert and awake. All of this the insurance company is and has been made aware of. Over the next few weeks they are resubmitting my case for review and expectation, according to my case manager, is that my long term disability will be discontinued. What should I do? When should I hire an attorney?