We do not have any influence on how Facebook handles this, as it is an external platform and the issue only occurs if the "Meta pixel for WordPress" plugin is used.
I would suggest you reach out to the plugin's support about it and ask them to have a look at the provided test site.
Anyhow, once again, when it comes to your WordPress Website, this issue only occurs if the same browser runs one tab in English and one tab in French at the same time and this is a very rare use case, that very likely will not occur if somebody visits the site.
This ticket was handling an issue that occurred on your website about the "Essentials Addons for Elementor" Post Grid Widget which displays different results in specific situations.
Our compatibility team decided to take further action on it, as the issue only occurs in very rare use cases.
I will get in contact with you about the Rankmath SEO issue on the new ticket shortly.