Sub tasks disappearing

[Bob]

I am entering several sub-tasks under a story on a Kan-ban board.  I entered 9 sub-tasks all of which were displaying under the story which is what I expected.  I then entered a 10th sub-task (of 12 total) and when I refreshed my screen all of the sub-tasks for this story and other stories under the same epic are no longer displayed under their appropriate stories.  I'm wondering what happened.  

[Alexey Matveev]

Hello,

Could you check that these subtasks can be selected by the filter, which you defined for this Kanban board(board configurtion -> general)?