Problem: The client is experiencing an issue where the translation functionality in WPML is not working despite checking WPML settings, language configuration, string translation, content translation options, theme and plugin compatibility, and clearing the cache. Solution: We recommend the following steps to resolve the issue: 1. Log in to your WPML account at https://wpml.org and delete the old site key associated with your site. 2. In your WordPress dashboard, navigate to Plugins → Add New → Commercial and click 'Unregister WPML from this site'. 3. Once the page reloads, click 'Register WPML'. When prompted for a site key, click 'Get a key for this site'. 4. Complete the site key wizard in your WPML account, ensuring to set the site as a Production site. After completing these steps, test if you can create and complete translations successfully. If the issue persists, please provide the exact steps you followed so we can investigate further.
Please note that this solution might be irrelevant if it's outdated or not applicable to your case. We highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If you still need assistance, please open a new support ticket at WPML support forum.