[Resolved] Uncaught InvalidArgumentException: item should be a Collection or an array or an object

Before we investigate this issue further, could you make sure your server conforms to our minimum requirements?
https://wpml.org/home/minimum-requirements/

Based on provided debug information, I can see the following - WP Memory Limit: 40M.

Could you set WP Memory limit to at least 128MB?

https://wordpress.org/support/article/editing-wp-config-php/#increasing-memory-allocated-to-php

So just add this into wp-config.php file:

define('WP_MEMORY_LIMIT', '128M');

before this line:

/* That's all, stop editing! Happy publishing. */

If unsure on how to set this, you can consult your host/server admin to do this. After you increase this value, you can confirm it by checking on WPML -> Support by finding the “Memory limit” value.

Hi,
Thanks for contacting WPML support.

Could you please check if the issue persists in a minimal environment by following these steps?

- Deactivate all the plugins that are not related to WPML.
- If the issue is gone, activate one by one to see with which one there is an interaction issue.
- If you still see the error, switch for a moment to a WordPress default theme like Twenty Twenty-one and check again.

❌ Please backup your database and website before performing the above test ❌

Kind regards.
Mohamed

Hi,

I couldn't find any similar reports with the same error and I can't reproduce the issue on a clean installation with the latest versions of WPML, ACF and ACF Multilingual.

This could be a conflict issue between ACF Multilingual and another plugin on your site, also it could be caused by a corrupted database entry related to the plugin settings.

To best troubleshoot the issue, kindly create a copy of your site and provide a link to download it. You can use the Duplicator plugin (https://wordpress.org/plugins/duplicator/).

The plugin will create a package file that you can download then upload again to Google Drive or Dropbox and share the download link in the next reply which I have marked as private. Then I’ll escalate this issue to our developers for further investigation.

Please check here for more details: https://wpml.org/faq/provide-supporters-copy-site/