Problems with product variability?

Question

WordPress

Hello, I am using the WP All Import plugin to import products from csv - but there is one problem. And specifically with some products.
There is a product that has sizes, these sizes are in sku "ER200.R.PX.6572" - 65-72 is the size. So I transfer 3 such products (variability), I get a large list of sizes (at the same time, they are transferred with different prices). But after importing, when viewing a product, there is everywhere one price for all sizes, and each group of sizes should have its own size.
With products that do not have such logic (adding sizes via sku by such groups), everything is fine.

As it should be
45-50 size - $500
51-56 size - $1000
and so on.
Maybe someone faced this?

I do not need a ready-made solution, just to suggest what is the reason - why woo combines them into one product and puts one price (of the very first product)