Intercontinental Exchange Java Professional interview questions

Total 4 rounds, first round was hacker rank test. After shortlisted, second and third round happened in one day. Second round was pure technical. Basics of Java, Spring, Hibernate and existing project details. Third round was related to the designing and cloud related questions. I was able to get through it. After one week, HR scheduled one more round with US colleague. This guy was completely unaware that this was my fourth round. He started from beginning. Java basics, coding questions, sql etc. I was able to get through this as well. Trouble started from here. HR called me to get the documents and I shared those. After this HR went silent. No communication. This entire process took more than a month. I was not expecting this to happen from an organization like this. I suspect is that they kept me on hold until they found some one with lower pay. If you are not interested or something is not working out, you should tell it upfront. Don't become a ghost. Wasted my time and efforts. Completely Unprofessional. Guys don't waste your time.