Hi there @arithiel,
Thank you for reaching out to the Community and for your detailed explanation. We're happy to help.
Can you head over to this post and follow the steps that's provided in the Solution of the post. This will hopefully help you with removing the device from your account.
When it comes to you not being able to connect to Echo, can you follow the steps bellow:
Let us know how it goes 🙂
Take care!
How do you Get Rid of that Echo Dot
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