Amazon firestick won't connect with Aazon.com

I replaced my extender with a more powerful one (EAX12). Firesticks worked fine before. Now none of my Firesticks will connext with Amazon.com. I have restarted Firesticks and router many times. I also bought a new Firestick, same result. Laptop and smart phone work fine through extender. I moved 1 of the firesticks to my main wifi router, same error message.