Missing code in shipping line from draft order checkout

Hi! This week something stopped working on our draft order invoice payments. We create draft orders through the GraphQL API, selecting a handle for the shipping rate. We used to get the correct code at the shipping line when the customer paid the invoice. Since Wednesday, we receive a shipping line with code custom and origin shopify. We have not changed anything, and marking the draft order as paid from admin gives us the correct code. Did something change that could have broken payments on draft order invoices?