Same happened to me just now.  I didnt answer or leave my info either.

Didn't answer when my phone rang, but called back. Went straight to a VM that said "Hello, and thank you for your interest in learning more information about what you just heard." And then they wanted me to leave my name and number again.  Of course I didn't.  I didn't receive a voicemail from this company, and the voicemail didn't say the name of the company.