Shell Machine Learning Engineer interview questions

Interview process was smooth and I was getting feedback from the HR within few hours after every round. After my all rounds were over, I got a mail from HR that I have cleared the interview. After this for around 3 weeks there was no communication from company side when I tried reaching out to HR he wont pick my calls and once I tried from different number he picked my call and said he will share the next steps. After that one month passed and didn't get anything, no communication , even I mailed other people who were in cc during my interview process.