Jewlr Customer Service Representative interview questions

i had one interview with some guy that went well, and then i met with the manager, and then i met with another girl on the team. all three interviews went well and i left feeling good. i got a call the next day saying i got the job and i was so happy. they needed me to come in and sign some papers. when i got there, i was bombarded into another interview i wasn't prepared for and that cost me the job. i told the HR lady that i was offered the job already and that i came to sign papers, hence why i came in wearing shorts (this was in the middle of summer) and with a coffee in my hands looking so unprofessional. she apologized and mentioned that the guy who did the interview didn't have the authority to offer jobs. i was taken aback. i was 100% honest in my answers which also probably cost me the job, but i found it so incredibly off putting and rude with the way the interview process was conducted. im actually very glad i didn't end up working there.