List Orders - incorrect order_type returned for OPEN LIMIT orders

when there is a limit buy order resting in the book, if I query the get order endpoint with the order uuid, all fields look good: status is OPEN, order_type is LIMIT.

But when I use the List Orders endpoint with status OPEN, the same order is returned but its order_type is UNKNOWN_ORDER_TYPE.

is this a bug or am I doing something wrong?

Thanks in advance.