I contacted help desk who said there is a known bug in updating/correcting an email address in a specific contact. They offered the below workaround, but I still can't figure out how to do or what the below means.
I keep getting error message "This email address already exists in your account." (which isn't the case)
From online chat w/help desk:
While we work on an overall fix, we have the following solution to offer you in the meantime, you can try this workaround.
As a workaround please add the email you're attempting to change it to, using the "Type or Paste Contacts" option.
Then, change the email address to something different, ie "test@test.com", but DO NOT delete it yet.
Once this is done, you should be able to update the original contact and delete the contact you changed in the previous step.
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