It is most likely Ft. Leonard Wood Mental Health making a follow up. They don't leave messages for obvious reasons.

Received call from unknown source. Did not answer and party did not leave message.

i didn't recognize the number, so i did not answer. i then looked up the number online, which gave me this page

I get regular calls fromthis number saying it is about my credit. I just hang up and do not listen but the calls are very annoying and I want them to stop.

when called wouldn't give info

We have received calls from this number at least 16 times beginning at 10:45 p.m. (E.D.T.) the evening of The first call started off sounding legitimate, briefly, then I knew it was a prank. There were at least 8 calls between 2:45 and 3:30 a.m. Four more this afternoon (4/26) between 3:30 and 4:00 p.m. Right now they are going to my answering service, and they are keeping track. Going to the police Monday morning. Many calls have been sexual in nature. It appears that he knows what business we are in, also.

I keep getting calls from this number. I have no idea why they keep calling because we never pick up.