The Eero does not support WPS at all. I do have a workaround if you have an old router. However, adding a WiFi extender is not the correct way to extend the coverage of an Eero, as it is old technology. You will need a second Eero to do this so as a Mesh network is formed. This is the way that Eeros are supposed to be used.
From the 29th of March our TalkTalk Community will move to peer-to-peer support and the TalkTalk team will no longer be here to support with queries. Don’t worry we still have plenty of ways to reach out if you need to speak to TalkTalk directly. For more details check out the link here
How to contact TalkTalk Broadband - TalkTalk Help & Support
