Woocommerce not setting correct attribute value?

Question

WooCommerce

When adding the first variation programmatically using the REST api, the wrong attribute value is assigned, it can be seen in the database that the desired value has been created, but it is also automatically created with the name of the product, and it is bound instead of the desired one. Also, for the variation attribute, the value is not set, from the possible values ​​\u200b\u200bbound to the product.

All this happens only in the case of adding the first variation to the product, then everything is as it should be. If the product already has some variations, then adding it immediately works correctly.

Is this a woocommerce bug? Will the update help?