Telemarketing calls that won't stop

I work for a health food store in Orlando and we haven't sold their product in 5+ years yet still receive almost weekly calls from them. Sent a cease and desist letter from our lawyer they continue to call. They claim they have received coupons from us, or check your shelf is it time to reorder, both lies to try and receive an order. Never, never order their products you will never stop being harassed.