I moved to a new theme on my website and clicked UPDATE. Now I don’t have an option to sign in as Admin.
Did you install WordPress in the root directory? If so, try: http://example.com/wp-admin/ and replace “example.com” with the URL of your website.
Were you able to resolve this issue? If not, please submit a support ticket and someone will reply via email asap.
In the meantime you can go to codex.wordpress.org for further assistance.