You might have noticed that Discourse creates one account per email address, so if you sent emails to the ODK lists from two different email accounts, you now have two usernames. Sad!
We are working on a way to merge those accounts, but until then, what I'd recommend is to pick a primary account, and for the secondary accounts, append -Inactive to the username and (Inactive) to the name. This way, if community members want to @mention you, they pick the correct account.
For example, if you have two accounts, rename the second one like so:
- Username:
Beyonce_Knowles1
Beyonce_Knowles-Inactive - Name:
Beyonce Knowles Beyonce Knowles (Inactive)
Then you might want to disable the summary digest on that inactive account to minimize the email you get.