I set my package name and company name in player settings but arcore change his after i build. 
hi,
Refer to script: Assets/GoogleARCore/SDK/Scripts/Editor/ExamplePreprocessBuild.cs and find the method name ‘ExamplePreprocessBuild’. You will see the Product name and Package name were hard code. Change these with your own names will fix your issues.
Hope that help.
#EDIT:
anotherway: you create another scene (could be the clone of that scene you want to build) , then add to build settings to build that new scene. Since the scene you’ve just added is not the scene in the database, it will not change your package id and product name.
