AstraZeneca Associate Scientist interview questions

I applied online and received a phone call about two weeks later. The caller asked if we could chat, but it was right before my biology lab, so I asked him if he could give me a callback or an email with his availability and I’d contact him. He assured me he would send an email, but I never received it. After waiting two days without any response, I reached out to the number that called me but couldn't connect, so I left a voicemail. When I checked my candidate homepage, I saw that my application was no longer under consideration. I was really sad to miss the opportunity to work for my dream company, but I also found this experience extremely unprofessional and disappointing. Normally I don’t answer calls from unknown numbers, but I did that one time because it was from Maryland, where I had applied to the AstraZeneca Gaithersburg site. In my previous job applications, all interviews were scheduled in advance, unlike this unscheduled call. It’s unrealistic to expect candidates to be available at any moment for an interview, and it actually raises a red flag for your company if candidates are just waiting around all day.