You have changed your site URL and you can no longer save your pages or posts under WordPress ?
When you click on the update button into the editor, it spins and never stops.
First, you have to make sure that you change your URLs correctly.
Please follow this official guide to be sure it’s done in the good way.
After you followed all steps, if the problem is still there, try to clear all caches:
- Your browser cache
- Your website cache
If you changed your DNS recently, please wait for 24h to be sure that everything is fine.
If the problem is still present, you should try to manually reset all your plugins.
Last but not least, you should check what is your Apache root folder on your server. Try to put your WordPress folder as the default Apache folder.