Wifi Calling isn't working

Hi there! My father and I have moved to a new place where there is very poor At&t service/signal. So we got wifi for the wifi calling feature of our plan. But it isnt working. It works with the wifi at our old house but no the wifi at the new house. Now both my father and I can connect to wifi with no issue and use it to surf the web. But it is the wifi calling wont work. We have already called the 611 number multiple times but everytime we do the call drops due to the service being poor to none. And one lady kept talking about service/signal. Im just very confused and need help. I just got a new phone from At&t and dont want to switch carriers.