Was contacted by a recruiter and started with phone interview followed by 2 technical interviews in virtual onsite

Phone interview:
Question related to https://leetcode.com/problems/text-justification/ . Started with an easier version and then enhance for more complicated scenarios
Result: Positive

Virtual Onsite
Interview 1:
Question1: Related to vertical ordering in binary tree. https://leetcode.com/problems/vertical-order-traversal-of-a-binary-tree/
Question 2: Merging sorted linked lists
Question 3: OOD
Was able to solve and code both optimally

Interview 2:
Question1: Related to merging intervals
Question 2: Design underground subway system, exploring corner cases
Was able to solve both but interviewer was only interested in approach for 2 so didn't code it completely

Final Result: Reject

I was quite surprised because interviews couldn't have been more perfect. During the entire time I walked through the approach starting from brute force and then come up to most optimal solution. Not sure what went wrong
Feedback was very generic "we look for fluency in data structures, algorithms and problem solving skills". I do not think it makes sense.

Preparation: Solved 315 leetcode (20% Hard, 60% Medium, 20% Easy)
Covered the problems over the last few years but really started proper preparation from last month.
I was also rejected from FB onsite previous month but probably will talk about that experience in a separate thread.
Slightly demotivated with back to back onsite rejects at FB and Bloomberg!