MIT Lincoln Laboratory Engineer interview questions

I met a recruiter who is also an engineer and alumni of my school at a virtual career fair, where I shared my resume. We scheduled a phone interview for a couple weeks later. The interview was about 1 hr long mostly about my experience and interest, with time for me to ask questions.

Received email notice of desire to schedule interview and filled out necessary forms. I was then called by a member of talent acquisition but they left no message and did not return my call or subsequent email. Unprofessional.