My dev and shipping package do download on first install

what the… what did i do ?

when i package my game for android (dev or shipping) and i try to launch on it on my android device the game dont install like before but it dowload something (download is size of obb) then it fail to install “xapk error”

what is this sorcery, i never tell anywhere where to download something -_-

before my game was installing and running fine, how i disable this magic download o_O

here is some log

09-06 13:42:58.776 17446-17446/? D/UE4﹕ … UI setup. Checking for files.
09-06 13:42:58.778 17446-17446/? D/UE4﹕ Checking for file : main.44.com.Sk3lGames.HammerTime.obb
09-06 13:42:58.778 17446-17446/? D/UE4﹕ which is really being resolved to : /storage/emulated/0/Android/obb/com.Sk3lGames.HammerTime/main.44.com.Sk3lGames.HammerTime.obb
Or : /storage/emulated/0/obb/com.Sk3lGames.HammerTime/main.44.com.Sk3lGames.HammerTime.obb
09-06 13:42:58.779 17446-17446/? D/UE4﹕ … Whoops… missing; go go go download system!