I had two interviews, one initial screening interview over the phone with a recruiter and then a zoom interview with the hiring manager. For me, both interviews took about 35 minutes. The first interview was more informative, explaining the details and expectations of the job and asking questions about my resume and past experience. The second interview consisted of several situation and behavior based questions ("Tell me a time when...". The best way to prepare for this kind of interview is reflect on past professional experience and come up with examples and stories that emphasize your soft skills that relate to customer service skills, such as persuasiveness, flexibility, leadership, empathy and communication/listening skills. Make sure that when you're answering the question, you're clear why that example applies to the question and you can tell stories clearly and concisely.