This number keeps calling and doesn't leave a message. It must be dodgy.

Unknown number calling several times with no message.

Like others, have received a call from this number, wait for someone to answer, and nothing but silence. Clearly waiting for the call centre to pick-up. Number now blocked

Do not even hear the phone ring. Never leaves a message. Blocking it now.

This number has called 8 times in the past 3 weeks.