Yes, I understand what happened to you.
Here is the output by the name of this product
that is, this is a product with sku_id=8527 - which you consider to be a duplicate
https://box.lanita-shtor.com.ua/admin/shop/products/10499/edit/and here is the issue of its constituent SKU
in fact, everything worked correctly (see the screenshot in the attachment) - the correspondence id=8527 was taken as the price of the goods, and 1417 - as the price level "Wholesale price (from one roll)"
and this product
https://box.lanita-shtor.com.ua/admin/shop/products/6688/edit/ - well, apparently you previously had 1, without a price level - and then supposedly a price level was not added to it (in this case, a duplicate would not have been created), but a new product was created and this one allegedly became a price level (we have added a price level, old products are not deleted)
in fact, what you need is to figure out that you really have a double, which is already registered in another product as a price level - and delete such a double.