Your WordPress site might stuck in maintenance mode after a failed update, which is either the result of the plugin/theme provider’s server issue or your server’s issue. In this case, you cannot log into your admin panel or view your website. All you see is: Briefly unavailable for scheduled maintenance. Check back in a minute.
There’s a very simple fix to this issue:
Log into your web hosting panel
Go to your web hosting service provider’s admin dashboard or if you have FTP access you can browse root files through FTP login, too. And then find the “File Manager”.
View this video on YouTube: Heating
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