Silent Cave unique map - neither completion nor atlas point

Today I've entered T11 Silent Cave unique map, after using all small essences and using Vaal on them I approached big essence, vaaled it, killed it and no quest item for atlas points dropped.
There are 0 monsters left, but Map Objectives are still not complete and states same thing "Defeat the Imprisoned Boss"


I've read some reddit posts and ppl got same Silent Cave completion issue. Please address this cause those are atlas points which are already hard to acquire.