Prior experience : Technical support in MNC
Current CTC : 5 LPA
YOE : <1 year
Degree : Mechanical Engineer

OA Round 1 :
Asked some basic questions about programming and aptitudes . After a week HR called out for 2nd round.

Technical Round 2:
It is a basic programming round where they will check you basic concepts in Data structures and algorithms.
Totally 7 problems were given to me and solved all of them. Immediately HR told me that I have been selected for next round.

Technical Round 3:
This round we need to solve the problems using OOPS concept and they given me 3 problems and I solved it.
HR told that I have been selected for next round.

Technical Round 4:
This round he gave me one problem and I took some time to understand and finally I solved in an efficient way.
He gave me one puzzle to solve it. But I couldn't solve. Then he told me that I have one more technical round.

Technical Round 5:
This round HR asked me 4 puzzles and one programming question and 2 aptitude question. It went well and I can able to solve all the questions . Interviewer said HR will contact me soon and I felt like I will possibly get this job .

I haven't heard back from them but I know zoho don't send rejection mails .

My negatives (might be the reason for the rejection)
1.I coded in C++, and I don't know java well..The interviewer asked me do you know java and I said yes but I haven't been in touch with it.
2.My company has 3 months notice period and the interviewer asked me weather I can break the notice period or not and I said not sure.
3.Since I am from mechanical background I did some projects using HTML ,CSS and React and I haven't done any projects using C++ or java.
4.My current role is technical support and I don't do coding there.

Any suggestion for me to become a software developer or any other things I need to work on?