Keeps calling and then hangs up. When you call back, there is an engaged signal.

Called and hung up after a couple of seconds. Pest

Called our office 3 times in the space of 20mins on a Friday night then once on the Saturday. Tried calling back, engaged tone.

rings and hangs up

Asked for me by name, but I didn't confirm my name to the caller. I asked what it was about and the person hung up. Tried to call back the number and it hangs up immediately.