I can't see any grey lines suggesting these are replies to a higher level comment, so I'm assuming they are "top level". In which case, this is how it's SUPPOSED to work. The most recent (top-level) comment is shown at the top of the list, the oldest at the bottom. Replies to top-level comments are then listed in chronological order with the first reply first, and the latest last. Replies to replies work the same, as do replies to replies to replies ... etc. This is how most websites present comments and - right or wrong - is the generally accepted "correct" format.
Er ... unless I'm misunderstanding your comment?