curl --location -g --request POST '{{BASE_URL}}/admin/draft-orders//edit/shipping-methods' \
--header 'Content-Type: application/json' \
--data-raw '{
"shipping_option_id": "string",
"custom_amount": 0,
"description": "string",
"internal_note": "string",
"metadata": {}
}'
{
"message": "Discount must be set to dynamic",
"type": "not_allowed"
}