FIS Senior Lead Engineer interview questions

"TOTAL WASTE OF TIME AND ENERGY." The first round happened over the call. Then I got a second-round call after 2-3 days which was told to be the final round.. The interviewer took my interview for 1 hour in which he asked me about my projects and told me how the automation practice works in FIS. After that next day, I got a call from HR asking about scheduling a third round, and told me that this will again be a techno-managerial round. The interview was scheduled for Tuesday which was then rescheduled to Wednesday at the last moment. In my third round, The interviewer asked me few questions related to my projects and a few related to general puzzles. He looked very happy with my responses and then after almost 3 weeks I got a call from HR saying that I have cleared the final round and would like to take have an HR discussion with me but before that she asked me to submit all my educational, professional, Identification documents and Forms in a day. Once submitted after 2 days the HR discussion happened and I agreed to all their terms and compensation. In that call, she said that she'll release the offer letter within 2 days. And boom, the offer letter never arrived in my Inbox. I tried reaching her but she didn't respond. At last, I lost hope and stopped thinking about FIS. The process literally took more than 40 days with no outcome. One suggestion to the hiring team is that every candidate deserves to know the status of their candidature. ( you just have to send a mail with the status). Because as a candidate, we also put in our efforts, time, and energy in going through the process, it's your responsibility to let us know the results. FIS being a fortune 500 company should have its values and must provide a positive experience to any candidate who is passionate to work with them.