IBM Software Developer interview questions

Two sessions. First was put on team of aroung 15 people to solve a puzzle, each person has couple of cards. Two of IBM watched us as we try to solve, Second session was logic/reasoning questions. At the end, they only selected two peopel, seems like the selected the two most spoken people in the first session.

I received a coding assessment to do within 7 days. It consisted of 2 questions, and I solved both. But still got rejected for unknown reasons. Would be great if they provide a feeback as to why they're rejecting.