Amazon Operations Manager interview questions

I got the email from the recruiter and we set up an interview. The interview went great. The usual amazon 14 LP and behavioral questions. 2hrs after the interview i got a call for the hiring manager interview and we scheduled a time for it. On the day of the interview, I logged into their amazon chime meeting and waited for a good 15/20 mins. Upon no show, I emailed the recruited and the replied back with “oh i am sorry position was filled because someone was already in the final round when we cleared you for second round”. Extremely unprofessional and unfair. How did they close the hiring without giving everyone a fair and equal opportunity!!

Phone Interview (first interview). Conducted via Phone. Approximately 40 minutes. Some basic questions, some simple math problems, and time for Q&A at the end. Very comfortable, put at ease, low threat.