Does anyone know if Medicare Advantage Insurers are required by law to provide contact information for claims. I have a Medicare Advantage I have tried to contact several times but the claims office is a different number and is not listed on the card or on the EOB. Left many messages at the number listed with no return call. Finally got a person today and she gave me another number to call for claims. Chose to hold for 20 minutes no answer, left another message. The time for appeal has passed as it was 60 days but I still haven't received a call back. Suggestions???