Are you trying to login to your WordPress website, but it failed?
Do you try to reset the password, and you get the error ‘Could not save Password Reset Key to Database’?
That simply indicates that there is not enough free space left on your hosting account, and WordPress is unable to write new login information into the database. As the database is part of the hosting space, you’ll get that database error when you fill-up the entire available disk space of your account. That can happen if you created several staging sites or if you uploaded too many large files like big images on to your website.
A more common reason for this issue can be substantial backup files created by your backup plugin. Backup files need a lot of space on your system, which can quickly fill up the entire available webspace.
So to fix the error, immediately log in to your website using an FTP client like the Filezilla program or the File Manager in your cPanel hosting dashboard.
Then go to the media folder
wp-content/uploads and check there for large files which you can delete, for instance, backup files with the ending .*zip or large media files with the file extension *.tiff, *.png, or *.png.
You should never use the *.tiff format, though. This one uses a lot of disk space, so it’s better to use *.jpg instead of that.
After, open your WordPress website and try to log in or to use the password reset function again.