India’s Chandrayaan 2 moon mission launch was canceled because of a faulty plumbing issue in its upper stage cryogenic rocket engine.
In the next few days, they will open up the plumbing system of the cryo engine stage and check what was the reason for the drop in pressure which should be a leak.
If the problem could be fixed within a week, then they will try another launch by the end of this month. If it is not launched this month then the next launch window is in September.