Character mistake: The alarm system has two codes; one (7466) that works properly and the other one (7465) that appears legit but would call the cops as well. Sarah is supposed to give the legit code, but before being cut off she says "774..." That would have not been a valid code. (00:15:20)
Character mistake: When the robber taunts Kyle, and he tells him that he does not hear the cops and the alarm...he's kinda not getting the point of the 'fake' code that Kyle was trying to use. The alarm was not gonna make any sound, it was going to be a silent one. And he knows that. (00:15:55)