Person 1: Flipkart.com sends the ordered materials to your home via post within 2-3 business days.
Person 2: Meh, I have seen them being late; one of my friends got his ordered material after 10 days!!
Person 1: I would say that is a out of pattern case!
So what is the best way to say "out of pattern" here? I want to mean a "discreet" occurence i.e. which does not usually occur. "Discreet" is the word I use in my mother tongue in this case. Can it mean the same in English too?