Theyring nearly every day and don't leave a message. Is there a way to block them ?

SPAM

Called and hung up immediately on me answering... no doubt it was an automated dial just to see if a real person picks up the phone, and whatever scam calls I'm going to get as a result will follow from another number. Another one to block.

I called back number (02) 8520 4072 spoke to a guy but did not hear the name of the company properly on the recording.

Selling combined gas and electricity packages.

rang number back after receiving 2 calls from this no. - they would hang up after I answered - got "Jenny" who just wanted to talk about my electricity account !!!!