Siemens Developer interview questions

Round 1: I received a mail from Siemens for a online test. It contained basic OOPS concepts and Java question and 2 simple programs. I received a mail that I have cleared this test. Round 2: I was given interview time for 12pm, yet I have to wait for 1:30hr. Then first round started the interviewer was really friendly and nice. He started with tricky questions of constructor and overriding, I was not able to answer them. But interviewer encouraged me anyway and continued with collections, Funtional Interface and SQL I was able to answer all of these question efficiently. He also asked some questions about REST, Spring and AWS and I answered them pretty okay. Interviewer then asked me to wait outside, 20 mins later HR told me I have cleared the round. Round 2: This round was taken by Siemens Chief Architect. It was mainly centred aroud my previous exp. , my current role and resposibilities. Interviewer asked some basic questions regarding docker, Parallel streams, AWS. Then he asked me what have I done recently of which I most proud of, I answered it in two parts one where I implemented something good technically than I added an example where I implemented something complex according to functionality of my project. I was also asked how would I rate myself in learning new technologies. I was also asked about my project architecture and why certain technologies are used in my project. I cleared this round. Round 3: This round was with Chief RnD of Roads(India), he didn't asked anything technical. This was more of a HR kind of round. Questions regarding strength, weakness, current CTC, expected CTC etc. One week later I was informed that I was not selected.