ION Group Software Developer interview questions

A totally unprofessional company. They take coding rounds, selects you for the job and then won't send you offer letter. When you ask HR for the offer letter, they will keep asking you to wait for another week else they won't pickup your call or won't reply to your mails. It has been a month that I haven't recieved an offer letter and I am not keeping any hope of having it either. I am quite adamant about declining the offer whenever I am going to having it. My process started with a online coding round followed by 2 technical rounds, one lasting around 2 hours with 2 interviewers and the 2nd one lasting around 1 hour with 1 interviewer. Then followed by a round with ION India head. In the technical rounds, they tested all of my technical skills like coding, design, projects, puzzles, thinking ability. Interview rounds were good but I wish if the people in this company value the time of the candidates who have applied and act professionally. And rest is the rating of the company which is publicly available on Glassdoor and there such acts depicts that they aren't trying to improve their rating in any way.