Hi bdunphy,
You can change the Sonos registered email yourself in the Sonos app. Just go to More > Settings > Sonos Account and click transfer. (It might be hidden under the keyboard in some mobile apps). Also, if you need to change the registered email, click sign in, and at the bottom, you can say you don't have access to that account or transfer to a different one.
That'll let you put in the new email address you need to use.
You can also find some
more details here.
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