If your WordPress website is only displaying a white page, there might be several reasons for it.
The most common causes are:
Maintenance mode is still active
If the maintenance mode is still active, a file named ".maintenance" should exist in the document root of the website.
Delete this file and the website should be displayed again.
Incompatible Plug-In
If an incompatible plug-In is responsible for the white page, you can check the error logfile for an entry of said plug-In and deactivate it, by renaming the plug-In in the WordPress plug-In folder. The error logfile can be found in the Control Panel on the server overview at "Websites" - "Logs".
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