Hartford terminated my benefits just like that

I worked as an over-the-road truck driver for Walmart for over ten years, and paid long term disability payments through my employer for nine years. Last year, I had to undergo surgery for Spinal Stenosis in my back and have been unable to work. The Hartford Insurance Company paid me benefits until today, terminating my benefits just like that. I am still under my doctor’s orders not to return to my job and has since had to let my job go because of company policies regarding leave time allowed. Now Hartford decides that my benefits don’t extend to 67 years of age as promised – but one year. What shall I do? No income as of today, that was so wrong.