We migrated our site to a new account and had several issues that the hosting service helped resolve. When I was able to login, I deactivated the plugin, but the Coming Soon page remained up. (We don't have and cache plugins.) The hosing support then tried to resolve the issue. Whatever they did now displays the following message on the site:
Fatal error: Call to undefined function get_header() in /home4/jugz1/public_html/index.php on line 2
Support said because the plugin was activated on the original site, this issue arose because it couldn't be properly deactivated on the new account.
How can this get fixed?