Problem: You are experiencing a recurring issue with the WPML plugin where after translating pages and posts, the backend functionality of your site gets corrupted, and the file admin-ajax.php throws a 500 error. The error log indicates a fatal error related to a function call on a null object within the WPML plugin's code. Solution: We have identified that the issue might be related to the PHP version compatibility with WordPress. Currently, your site is running on PHP version 8.3, which has only Beta support in WordPress. We recommend switching to a stable and compatible PHP version, such as 7.4 or 8.0, to see if this resolves the issue. You can check the PHP compatibility details with WordPress at this link.
If this solution does not resolve your issue or seems irrelevant due to being outdated or not applicable to your case, please open a new support ticket. We also 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. For further assistance, you can contact us directly at WPML support forum.
