Tell us what you are trying to do?
Create template and publish. But updating failed.
Is there any documentation that you are following?
No
Is there a similar example that we can see?
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What is the link to your site?
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Nigel
Supporter
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I saw on your video that you were trying to save a Content Template and it showed an Update failed message.
There is likely to be more information in your PHP logs that explains why.
If you haven't already, turn on the debug log by editing your wp-config.php file and change the line with WP_DEBUG like so:
define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', false);
define('WP_DISABLE_FATAL_ERROR_HANDLER',true);
That will create a debug.log file in your /wp-content/ directory which you can examine in any text editor.
Try saving the template again and then inspect the log.
You can also check your browser console for JS errors, but I expect the more useful information will be in the server log.
Please share here what you find.