Energy scam call - don't pick up

Caller: (02) 8043 7136

Whatever you do, don't answer this number. "Shaun" from this dodgy company called our office landline, and we said politely "no thank you we are not interested" He immediately called back, said my receptionist had asked him to call back. I said she hadn't. He accused my receptionist of lying, and demanded an apology. I advised we would not be apologising and to stop calling our number. He said he would stop calling when we apologised. So far he has called 20 times in the past 24 hours, 19 of those calls being yesterday afternoon / evening.