I just did but no message was left

I never pick up. They call a few times they do not leave a message. I have never tried calling them back

They keep calling!  How do they even get my number?  They call back-to-back all times of the day and night!  I answered once but no one said anything.  Very frustrating!  Help get rid of them!

....to remove your comment.  The person you named in your post is likely to be an innocent victim of number spoofing.