The reason why those old stream appear at the top is because that is current default behaviour in EasySocial ordered by last modified dates.

For example : when the user like or comment on one of the older stream, the system will move this older stream appear at the top.

If you would like ordered by those stream based on the stream creation date, you have to modify this PHP file temporary :

Open this file JoomlaFolder/administrator/components/com_easysocial/models/stream.php and modify at line 33 locate the codes below,

private $streamPaginationSort = 'modified';

Replace it with,

private $streamPaginationSort = 'created';

In EasySocial 2.1, we will allow admin to choose what stream listing sorting behaviour their want from backend.

Hope this will help.