I have host mapping set up but visiting my Help Center redirects me to https://subdomain.zendesk.com. Why?
Check your settings under Admin > Settings > Security > SSL. If you have your Help Center host mapped but regular SSL enabled, users will be redirected to https://subdomain.zendesk.com. If you'd like, you can provision an SSL certificate through Zendesk in that menu, or you can upload your own.
If you're still running into trouble, please send an email to firstname.lastname@example.org, or see Preparing a SSL certificate for upload to Zendesk for more information.