The phone adapter plugs into the router, not the ONT. If you need more ethernet ports on the eero then a plugin switch will do the job, see here for examples:
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 - Help & Support.
