[Fechado] invalid value posted for product attribute

Background of the issue:
I am trying to add a variable product 'Lenses' to the cart on my WordPress site. The issue occurs specifically with the 'left-eye attribute' of lenses variable products. This problem is more frequent in the English version of the site compared to the Arabic version. I suspect there might be a synchronization issue between languages. Here is a link to a page where the issue can be seen: link oculto.

Symptoms:
An error message appears stating 'invalid value posted for product attribute'. This error occurs with many lenses brands, specifically with the left-eye attribute.

Questions:
How can I fix the 'invalid value posted for product attribute' error?
Is there a known issue with synchronization between languages that could cause this error?