It sounds to me like Cigna has either made an error or has given you incorrect information. The MA56 remark is addressed to the provider who has opted out of Medicare, not to the patient, and if your provider accepts Medicare assignment, then they are incorrectly stating that your provider has opted out of Medicare, which I gather from what you're saying is not true. The Medicare limiting charge applies to patients who DO have Medicare, not to ones who do not. Unless this is a Cigna Medicare replacement plan that your provider is not participating with? I would get on the phone with Cigna and get clarification from them of what is going on here and why they are stating that you are subject to a Medicare limiting charge if this is not a Medicare patient. Ask to speak with a supervisor if the representative can't give you a clear explanation for this.