The reason for the error should be visible in the error log. You can find it in your hosting area. If necessary, the support of your hosting can help you.
Alternatively, you could also enable debugging in WordPress. How to do this is described here: https://wordpress.org/support/article/debugging-in-wordpress/ – also here the support of your hosting can help you if necessary to edit the file accordingly.
In both cases you should be able to see what the cause is in the logfile.
Thanks, so I set the debugging after trying a restore or 2 from backup, but can’t see anything obvious in the output file that suggests what the issue may be? I did speak to my hosting support first who suggested the restore option and failing that disabling plugins. If I try this suggestion could that break my site?
Yes, it would be possible – as with any major operation in the database. Create a backup beforehand, preferably using the options provided by your host.
However, I find it strange that there are no entries in debug.log or error.log regarding the error that occurred. There must be something there. Did you provoke the error again so that a new entry would appear in the log file? If nothing appears, either a special error log is active in your hosting (which your host’s support team would have to clarify) or you are looking for the error in the wrong hosting.
It’s possible that the active theme is conflicting with WordPress or some of your plugins. Try switching to a default WordPress theme (like Twenty Twenty-One) temporarily:
Go to Appearance > Themes in the WordPress Admin.
Activate a default theme.
Check if you can edit the page again.If it works after switching the theme, the issue is likely with your original theme.
you could also try this
Open your wp-config.php file and add the following line before the line that says /* That’s all, stop editing! Happy blogging. */:
define(‘WP_MEMORY_LIMIT’, ‘256M’);
Save the file and see if this resolves the issue.
