Hi,
assuming as your info pack loading data to cube directly as per 3.x data flow.
So go to your cube-->manage-->request tab, see here how many failed requests are there.
if you have two requests then you can't run repeat delta option.
if you have one failed delta request then you can make it as red again and go to your delta info pack-->trigger it.
it will prompt for repat delta, yes you can continue with repeat delta.
Thanks