Dodgy telemarketers were trying to scam fees out of Australians wanting to be placed on the Do Not Call register, according to the communications regulator.
The Australian Communications and Media Authority said today it had received over 30 complaints in the past month.
It did not say whether or not anyone had fallen for the scam.
It asked people that received such calls to "get as much information as possible from the caller" before lodging a complaint with ACMA.
The Do Not Call register allowed consumers to block telemarketing calls for free for a period of five years.