The X social media platform is back offline in Brazil, a day after it resumed service in contravention of a judicial ban, the Brazilian Association of Internet and Telecommunications Providers (ABRINT) said.
The country's Supreme Court had ordered the network to suspend access in a bitter legal standoff with its owner Elon Musk.
The court found the company had "unlawfully, persistently and intentionally" flouted judicial rulings and would risk a daily fine of more than $900,000 (€806,000) for non-compliance.
X, formerly known as Twitter, said the restoration of its services in Brazil was "inadvertent and temporary".
In a statement, the company said it had switched network providers in order to continue providing services to its Latin American users, resulting in the temporary restoration.
"This change resulted in an inadvertent and temporary service restoration to Brazilian users.
"We continue efforts to work with the Brazilian government to return very soon for the people of Brazil."
Earlier, ABRINT attributed the return of X to an update of the app to Cloudflare software, which uses constantly changing IP addresses.
Brazil's shutdown of the platform infuriated Mr Musk and fuelled a fierce debate on freedom of expression and the limits of social networks, both inside and outside the country.
X has more than 22 million users in Brazil.
The hashtag "Twitter is back" was one of the most used in the country.
What is Elon Musk's feud with a Brazilian Supreme Court judge about?
Judge Alexandre de Moraes last month ordered X to be banned after Mr Musk refused to remove dozens of right-wing accounts accused of spreading fake news, and then failed to name a new legal representative in the country as ordered.
The judge also ruled that those using "technological subterfuges", such as virtual private networks (VPNs) to access the blocked site, could be fined up to $9,000 (€8,000).
Judge Moraes has repeatedly clashed with the South African-born billionaire after making it his mission to crack down on disinformation.
Last week, he ordered the transfer of about $3 million (€2.7m) from Mr Musk's companies to pay fines incurred by X.
He reacted angrily to the suspension, calling the judge a "dictator" and repeatedly targeting him in posts to his 198 million followers on the platform.
Brazil's leftist President Luiz Inacio Lula da Silva had hailed the ban, but his far-right predecessor Jair Bolsonaro was staunchly against it and welcomed the technical tweak that brought X back online.
"I congratulate all those who have pushed to defend democracy in Brazil," he wrote on the platform.
