Very disappointing process. Despite being selected for an initial interview, the conversation was cancelled on the day without any notification. At least the recruiter called back after I send an email and explained the situation - which was nice enough. It seemed that they provided an offer & hired someone just a day before, nonetheless considering you are scheduling interviews with candidates who take time out of their day to prepare for the interview, the right thing to do would be to conduct those interviews and afterwards provide the offer to the best candidate. Don't just overbook candidates and then cancel all future interviews on very short notice without even giving a chance for a conversation - that's just unprofessional.