Amazon Sde 2 interview questions

First I received an online assessment. They presented 2 leetcode mediums that covered dynamic programming concepts. Next, it was a coding round (Data Structures and Algorithms) followed by a system design round. There was a huge delay from when I passed the online assessment and had my DSA round scheduled for some reason. The system design round was scheduled for one hour but for some reason the interviewer took 2? They seemed all over the place