Sedgwick denied my STD appeal, is there anything I can do to get my money back?

Hello! My medical team all knows how unwell I have been. I submitted a 16 page document of tests and proof that I have been unwell to Sedgwick and they have denied it and have been taking my paychecks to “make up” for the time they don’t believe I was sick during my disability. They are telling me there’s nothing I can do about it but this seems very wrong and unfair. My cardiologist’s assistant was vague on the initial paperwork which caused this in the first place but my cardiologist himself agrees that I should have been approved based on my circumstances.