Agoda Back End Team - Engineer interview questions

I applied for a job which is based in Bangkok and i am from a neighboring country . Initially after applying through its website, A week after- two back to back rounds of interviews were scheduled. In first round, the interviewer asked me to code for some problems . First was to find count of first non repeating character and second was to find a subarray with sum. I instantly coded for same and then he told me i was selected for further session. This session lasted for 50 minutes. After 5 minute break, in second session, the interviewer asked me about data structures, then he asked me to implement merge sort algorithm and then he asked to write implementation for HashMap. Since i know how to solve all these, i solved all these with clear explanation of the code too. After 5 days, I got a mail today that I have been not selected with no proper feedback from team. I am damn sure it might not be because I am not able to meet the technical specification , but could due to any other reason. Anyways, i had to take a day leave to plan for their back to back interviews, it would be great if hr would have given a feedback atleast.