The interview process consists in three parts. First of all, you will be asked to present yourself, you should expect to talk about your relevant experiences for the job. Bear in mind to stress how important was to deliver a great customer service in your previous job and how successfully you achieved the result.
Secondly, the will go through several questions about your previous roles. Be prepared with clear and concise explanations.
Finally, they will ask HR questions. They have a sort of form to fill with 3 questions for each topic. The interviewer will choose one of the three questions. All the questions have been already reported here. I have studied for my interview preparing an answer for each question. Important: remind to use the STAR structure. You should be ready to "serve" an example for each question. Doesn't matter if it comes from real experience or not. It should look real and pertinent to the topic.