app crash immediately after call openIAB.queryInventory.

[minhit1805]

Hello, after call OpenIAB.init succeccsful.
public const string offter1 = "com.petgames.offer1";
public const string offter2 = "com.petgames..offer2";
public const string offter3 = "com.petgames.offer3";
private void billingSupportedEvent()
{
//_isInitialized = true;
Debug.Log("billingSupportedEvent");
OpenIAB.queryInventory (new string[]{offter1,offter2,offter3}); <-- crashing here
}