In a LinkedIn post on Friday, BrewDog boss James Watt admitted to “some costly mistakes” that sparked a string of events he described as “pretty grim.”

Multinational brewery and pub chain BrewDog—which is headquartered in Scotland but also has several bars in the U.S. and plans to expand into India, Ireland, and Italy—scaled rapidly thanks to crowdfunding.

Britain’s Advertising Standards Agency (ASA) ruled in 2021 that a BrewDog promotion offering customers the chance to win “solid gold” beer cans that had been hidden in regular cases was misleading. As well as being told they could keep the cans, winners had been promised £15,000 ($18,210) worth of BrewDog shares.

Some winners complained to the regulator, however, after discovering that the cans were actually gold-plated.

Referring to the promotion as “a £500,000 mistake,” Watt detailed in his post last week how the failed promotion had been “my mistake and mine alone.”

“Inspired by everything Willie Wonka I decided that we should hide 50 gold cans in cases of beer,” he explained. “We found an amazing goldsmith to make the cans for us and when they arrived at the brewery, we were blown away by how beautiful they were.”

In his enthusiasm for the promotion, Watt said, he misunderstood how they had been made and sent a series of tweets that told his followers there was a possibility they would find “solid gold cans” if they bought a specific case of beer.

“It was a silly mistake and it only appeared in around three of a total of 50 posts about the promotion but as it turns out, those three tweets were enough to do a lot of damage,” he added. “Those were three very expensive mistaken tweets that I sent out in my enthusiasm for our new campaign.”

Conceding that BrewDog “deserved the flak” it received online and in the media over the gold cans campaign, Watt said he decided to do something “radical” to fix his error.

“I got in touch with all 50 winners and let them know that if they were unhappy with their prize I would personally offer them the full cash amount as an alternative,” he said. “Furthermore, I promised to fund this myself so the business did not have to suffer financially from my mistake. All in all, it ended up costing me around £470,000 ($570,570)—well over two and a half years’ salary.”

Brewdog’s latest problem

Watt’s costly error with the gold cans promotion is the latest in a string of public mistakes Brewdog has come under fire for in recent years, with accusations of bullying, intimidation, and inappropriate behavior swirling around the firm.

In 2021, present and former BrewDog staffers wrote an open letter detailing a “culture of fear” within the company, with signatories demanding an apology for “harassing, assaulting, belittling, insulting, and gaslighting.”

The company has reportedly spent millions of dollars trying to fix its culture problems, with boss Watt publicly apologizing for former employees’ negative experiences at the firm.

Former staffers who spoke out in a 2022 BBC investigation have since told the broadcaster that they have felt intimidated or threatened since the program aired, with several saying they had been visited by private investigators.

Representatives for BrewDog did not respond to Fortune’s request for comment on those allegations.

In the run-up to the soccer World Cup last year, BrewDog stylized itself as the “anti-sponsor” of the event, criticizing host country Qatar over its human rights record—only to face a slew of backlash for its own history of questionable employment practices.

Last year, Watt spoke publicly about his personal struggles heading up the brewery, admitting: “at times in the journey I have been too intense, I have been too demanding… I did push people too far.”

BrewDog reportedly said last year that it had been valued at more than £1.8 billion ($2 billion)—but an earlier dispute over the company’s “outrageous” valuation was said to have caused an end to a potential partial sale to Heineken in 2018.