I suspect that the error is being caused by the PHP version. It is recommended to check by downgrading the PHP version to a stable one, which is PHP 7.4.
Thanks for the update. Since the issue persists even after changing the PHP version, would you please check if it is happening due to any conflict between the plugins?
Please make sure to take a full backup of your site and database before doing the conflict test.
- Deactivate all plugins except for WPML and its add-ons and check if the issue persists.
- If that solves the issue, start activating the plugins one by one and continue checking for the issue after each activation. This will help you determine if any plugin is conflicting with WPML and causing the problem.
But, if the issue persists even after that, then a closer inspection will require to understand the root cause. I would like to request temporary access (wp-admin and FTP) to your site to take a better look at the issue.
It would be better to have a testing site where the issue is replicated.
You will find the needed fields for this below the comment area when you log in to leave your next reply. The information you will enter is private which means only you and I can see and have access to it.
Maybe I'll need to replicate your site locally. For this, I’ll need to temporarily install a plugin called “Duplicator” or "All in One WP Migration" on your site. This will allow me to create a copy of your site and your content. Once the problem is resolved I will delete the local site. Let me know if this is ok with you.
IMPORTANT
-If you do not see the wp-admin/FTP fields this means your post & website login details will be made PUBLIC. DO NOT post your website details unless you see the required wp-admin/FTP fields. If you do not, please ask me to enable the private box. The private box looks like this: hidden link
