OC4 does not load the correct variant of the product in the cart

Hello,
I use OC4 version 4.0.2.3 for my site. I use default theme. When a customer load a variant of product in the cart, OC4 load the principal product and not the variant.

The "error.log" does not report any problems (report other warning, but it isn't a problem for run the OC4)

Other extension loaded is "OpenCart Default Extension", my pack language extension (italian language) and "Paypal checkout integration" extension.

Sorry my bad english

Could be this issue. https://github.com/opencart/opencart/issues/12338