News Corp-backed bookmaker Betr has been fined for trying to sign up a self-excluded gambler as a customer ahead of the Melbourne Cup race.

The Northern Territory Racing Commission fined Betr $20,655 for breaching the NT's online gambling code of conduct when it directly marketed to the self-excluded person with an offer to open a betting account.

The commission's decision said Betr representatives contacted "Mr M" by phone and text message in early October, shortly after Mr M had joined the NT's self-exclusion register.

Anti-gambling advocates say the case highlights the need to urgently implement the national self-exclusion register, which is yet to be rolled out despite being legislated three years ago.

"It's a mystery why this system isn't already in place," Carol Bennett, CEO of the Alliance for Gambling Reform, said.

"The national self-exclusion register is a bare-minimum measure to safeguard problem gamblers from being targeted by the industry, and the federal government needs to make it a priority."

The territory's self-exclusion register allows people around Australia to voluntarily cut themselves off from NT-based betting companies. The self-exclusion period can last months to years, or indefinitely.

Like most major Australian bookmakers, Betr is licensed in the NT and subject to its consumer protection rules. The territory's gambling code of conduct makes clear betting companies must not contact self-excluded people without their consent.

"Commission records indicate that Betr did receive a copy of the full list of self-excluded persons on 5 October 2022 which included Mr M's details," the commission said in its decision.

Betr declined to comment, but according to the NT Racing Commission's decision, it made submissions its sales representatives had sourced Mr M's contact details from "their previous employment".

It said the two representatives did not know Mr M was on the self-exclusion register when they contacted him.

"These communications took place between 5 and 10 October 2022 which was shortly prior to Betr's launch, and before its customer database had finished being populated with and cross-checked by reference to all self-exclusion data provided by the commission," it said.

The gambling agency said it had since told all its staff and representatives they could only contact a potential customer once they had verified the person was not self-excluded.

Betr burst into the gambling market in October by offering punters 100-one odds on all bets up to $10 in the Melbourne Cup.

About 48 per cent of its shares are owned by the Murdoch media empire, which recently increased its stake in the company.

In its decision, the NT Racing Commission noted the extensive experience of its senior management, including its CEO, former BetEasy boss Andrew Menz.

"Although Betr is a new licensee, the management of Betr … have been in the industry for many years holding similar positions within other Territory licensed bookmakers," it said.

"The Commission is therefore very disappointed that, under their leadership, affiliates and employees were permitted to contact any persons without having ensured the process of entering all of Territory self-exclusions into the Betr systems was completed."

Ms Bennett said her organisation had spoken to multiple problem gamblers who had received marketing material while on the NT's self-exclusion register.

"That's why there needs to be a stronger national register, and federal government has a responsibility to implement measures that are commensurate with the harm caused by gambling," she said.

"The national self-exclusion register is an important first step, but it hasn't even been implemented yet."

The previous federal government legislated to introduce a national register in December 2019 as part of its National Consumer Protection Framework for Online Wagering.

The Australian Communications and Media Authority (ACMA), which is responsible for the rollout, announced in July the register would be named BetStop and launched in the "the coming months".

Communications Minister Michelle Rowland said in a statement ACMA was conducting an "extensive security assessment", which it would conclude soon, of the proposed register.

"Ensuring that potential users of the register have confidence in its security will be key to its uptake, and accordingly, its success as a harm-reduction mechanism," she said.

Gambling industry lobby group Responsible Wagering Australia, which does not count Betr as a member, said it supported the rollout of national register.

However, it said it wanted stronger data protections in the wake of the high-profile hacks of Optus and Medibank.

"Millions of customer details of more than 100 online wagering operators are going to be sent to the register," a spokesperson said.

“One of the most important and critical issues that remain to be resolved is adequate cybersecurity and data protection for the sensitive personal information of wagering customers.”