Refund not sync

Hi,

I managed to import all the data from shopify to woocommerce, but I noticed that the refund orders were not synchronized in woocommerce, so the statistics are completely wrong.
Did I miss something ? I think that the problem is similar to this topic https://villatheme.com/supports/topic/partial-shipping-refund-not-synced/
Can you explain me what was the problem ?

Regards
Michel-Ange