You need to load up the receivers and take them back to their warehouse. They have to take them back, if they refuse, go up the chain to the warehouse manager, if he refuses, go up the chain to his boss. If they refuse to take the equipment back, then proceed to charge you for the equipment, then you have an argument, make sure you document everything, and if you take the equipment to them, and they refuse to accept it, then make the person refusing sign a paper saying they refuse to take back their aging receivers.
Never argue with idiots, they'll drag you down to their level and beat you with experience
This is CABL.com posting #323525. Tiny Link: cabl.co/mbwkj