Keeps calling...I think it is a scam

I have had 3 representatives in 3 days call me from AMG regarding my mortgage. Not one person can tell me what AMG stands for. They are calling from Barrington, Illinois. As I pressed each one as to who they are, they would only say I am Megan or Roy of Robert. As I talked, they would talk over me. I finally asked the last guy if he was a robot. He replied, no I am a real person. When I tried to confirm he was not a robot and asked for the color of his hair, he hung up as did the other two when I pressed for more information about the company. Megan said that I would have to ask the lender about what AMG stood for. LENDER??? WHAT LENDER???? They were trying to press me for if my home has retained it’s value and quoted my initial amount that I mortgaged. They wanted to know how much I owe now...Of course I did not give out any personal info, but I want these calls to stop and be blocked.