Someone from this number keeps calling and not leaving messages. Getting annoying...

i starting to get annpyed when i get a call from this number but by the time i answer they hang up?

do not call my phone......

do not call me ..........................

this number has been calling me almost everyday or every other day for the last 2 weeks. Most of the time they are calling me in the morning and waking me up. if i answer it hangs up instantly if i call back the call does not go through. How do i stop this? I wish i could get 5 mins alone in a room with whoever is responsible for this id break all of their fingers so they cant call me again!!