Caller ID says Richard Lopez.  I called back and they answered hello.  Conversation went as follows:
them:  hello
me:  hello, who is this?
them:  who is this?
me:  I missed a call from this number.  Who is this?
them:  can I speak with Belinda?
me:  No.  Who is this?  (I don't know anyone named Belinda)
them:  is Belinda there?
me:  No.  Who is this?
them:  click.