The coalition leaders behind nationwide pro-democracy protests that have drawn millions of Americans to the streets in recent years were frustrated when its Instagram account was temporarily shut down during its latest demonstration on Saturday.

The No Kings movement’s account went dark for several hours while protests focused on increasing early voter turnout were underway, sparking censorship fears.

Meta apologized on Saturday and blamed the account’s temporary suspension on an automated action that’s triggered “when accounts post, share or comment at very high frequencies”.

“Unfortunately, that automated action was clearly taken in error,” Meta spokesperson Andy Stone, wrote on X. “Everything is now working as it should and we sincerely apologize.”

“We have regained access to our accounts, but Meta still owes us an explanation,” the No Kings Coalition posted on their Instagram page, on Sunday. “Restricting communications about voting in the middle of an election is unacceptable.”

Organizers remained skeptical about Meta’s explanation that high-frequency posting triggered an automated response, and said members “posted only a handful of times and livestreamed to thousands”.

Senator Bernie Sanders also expressed concerns on Sunday, on X, saying that “billionaire ownership of the media” had resulted in the suspension of the No Kings account.

Despite the technical blip, hundreds of planned events continued. At the Lincoln Memorial in Washington, a band played for a few hundred people in caps and coats, many of whom were dancing and held signs saying “VOTE EARLY” and “HANDS OFF MY VOTE!”

In Atlanta, city councilman Michael Julian Bond told the crowd: “The constitution gives you one power, right? That is the power to vote. Are you gonna use that power?”

On the streets of downtown Los Angeles, protesters carried umbrellas to protect them from the sweltering heat and a band trailed behind them on a rolling stage, the New York Times reported; the crowds cheered calls for abolishing ICE and passing California’s billionaire tax.

The No Kings movement began last summer, in response to a broad set of concerns about federal layoffs, immigration enforcement and foreign wars. The demonstrations have continued to tackle a wide range of issues, and typically lean into anti-Trump fervor.

This year’s focus on voting ahead of the midterm elections is in part due to the supreme court’s gutting of the Voting Rights Act, as well as fears about Trump once again sowing chaos by baselessly calling election results into question.

No Kings organizers said they planned to recruit volunteers at Saturday’s events to mobilize in case of “election sabotage”, Leah Greenberg, a co-executive director of Indivisible, a progressive group that helps organize No Kings events, previously told the Guardian.