It sounds like your Amazons are flock-calling, which is a normal thing for parrots to do. They want to know where you are and if you're OK, and are waiting for you to respond. It often helps curb the squawking to answer back with a whistle, clicking sound, or simply by saying "I'm still here," "I'm OK," "Be right back," or something like that. In time, they may learn to whistle or click or repeat your phrase instead of screaming. Sometimes it helps to tell the parrot-- before you leave the room-- that you're leaving and will be back in a little while. That probably won't stop the flock-calling, but might tone it down a bit. Amazons are wonderful birds, but they can indeed be very loud, and very persistent.