Can't enter DLCMap

I am trying to create a DLC pak for my game . And I’ve done :

  1. Created a plugin named “DLC1New”
    2.Released my game.
    3.Released my DLC pak.
    4.Put my DLC pak into game content folder.

Then when I try to enter DLC map through blueprint or console , the game will open the startMap(StudioIntroduce) .
I don’t know why and what to do , please help me .

Besides , when I try to merge the game and DLC , the game will take about 11+GB .
However , when I depart the two , the game takes 10.6GB , and the DLC pak only takes 7MB.
So , I wonder if the DLC map doesn’t cooked ? But I’ve already add the DLC map into cook list .
Please help me , thanks!