I have needed a very long break from it, to be able to detach my mind from the other ones. Today, I came back to it and got it within a few tries.
Generally, for me, to have done similar levels before is more a counter than a help.
You know when the teacher says "this will be on the exam" and then you get to the exam and it was in fact on the exam but you've already forgotten? Yeah, that's me right now, after the first 5 levels.