Syetems not showing in action

Hello All, i triggered two actions with same manual group which has 5 computers. At the time of applying, 3 computers were online. But after starting those 2, one of the actions has started executing but the other one is not showing those 2 at all and now, one action is fully completed with 5 computers but the other one is still showing 3 machines, whereas all the 5 machines are up and running. Please suggest me what to do and why it happened?

Are the non-responsive systems subscribed to the site where the content came from?