I completed the JP Chalice of Tears. However at the Top of Volcano , the reward chest does not give Flask of Tears. I need it for Ember Bay Achievement. Is the the reason that the Ember Master is not activated on my profile ? Thanks.
Probably, yes. You need the collection active to be able to get it.
Necro mains either are masochists or become masochists after a balance patch.
Does it mean after the collection active, I have to run the JP again ?
Yes and it would have to be either on two different characters or two different days as well since JP chests are only lootable once a day.
You also need every checkpoint on the way up for the achievement/flask of tears.
The chest is lootable without the checkpoint, the flask of tears will only be rewarded if you went to all the checkpoints