Your forum account is your main-site account — the forum signs you in through the main site (SSO).
That means all account management happens on the main site:
- Email — change it on your main-site profile; the forum syncs automatically.
- Password — reset via the main site.
- Username — managed on the main site; the forum follows.
- Account deletion — handled through the main site as well.
If anything looks out of sync here, it will catch up within an hour of the change.