HSBC Universal Banker interview questions

telephone interview followed by face to face. whole process took 3 months to apply. background check took a month. asked questions like what sets you apart from the rest, tell me about a time you handled a difficult customer.

I applied for Universal Banker role in one of the London branch. In the job advert it was mentioned anyone who is looking for full-time, part-time, contract, temporary work can apply. Note - "I made it very clear at every stage that I am full-time student and looking for part-time work" First stage was submission of application, then after my application was selected I got the online assessment which consisted of behavioural questions (when I received email for assessment they changed the position name to Customer Service Representative). After the selection at previous stage I got an invitation for completing on-demand video interview which was again stated as for Universal Banker role, it consisted of 5 questions. I got through the next stage, which was zoom call with 2-3 interviewers for Customer Service Representative. When I joined the zoom call, interviewer said the actual role they are recruiting for is the Cashier Role for which they needed someone who can work full-time. He started interview on that note, and I knew that I would not be selected as I can only work part-time, still they wasted my time through such a long process. If you wanted to hire someone full-time, why would you not clearly mention? If all the roles are same - Customer Service Representative/ Cashier/ Universal Banker, then why to change the name of role at every stage? Why to waste the time of full-time international students?