I am trying to add a new size variation to a product I have live on my site. I have the Attributes set up correctly. However, when I add the new Variation which is XL, along with Regular Price and Stock Qty the new variation will not save.
The same issue persists with default Woocommerce theme Storefront too. So it’s not related to our theme.
Perhaps this is related to server configuration. We recommend you to contact Woocommerce support regarding the problem and mention that it happens with their default theme Storefront.