More than $2 billion has gone missing at one of Europe’s most vaunted tech companies. If it’s not found quickly, the digital payments firm may never recover. Wirecard (WCAGY) delayed the publication of its 2019 financial results on Thursday, saying its auditors couldn’t account for €1.9 billion ($2.1 billion) in cash. Then on Friday, the German company’s CEO, Markus Braun, resigned. Investors reacted by pushing shares in the company down by more than 75% over two trading sessions. “Without a very concise explanation in short order, we fear Wirecard is headed to zero,” said Jasper Lawler, head of research at London Capital Group. Founded in 1999, Wirecard was once considered one of the most promising tech firms in Europe. It processes payments for consumers and businesses, and sells data analytics services. The company, which has nearly 6,000 employees in 26 countries around the world, reported revenues of over €2 billion ($2.2 billion) in 2018, or more than four times the figure from 2013. Investors recognized its potential: Shares reached an all-time high above €190 ($213) in September 2018, the same month it replaced Commerzbank (CRZBF) in Germany’s list of top 30 companies. At that point, Wirecard was worth more than €24 billion ($26.9 billion). The shares closed at €25.82 ($28.88) on Friday, valuing the company at less than €3.2 billion ($3.6 billion). This week’s implosion follows a tumultuous 18 months for the company punctuated by allegations of fraud, attacks by short sellers and questions over its accounting practices. The success story began to unravel in January 2019, when the Financial Times reported that Wirecard forged and backdated contracts in a string of suspicious transactions in Singapore. The company denied the report, which was produced with the help of a whistleblower, but its shares plummeted. In February 2019, authorities in Singapore said they would investigate. Another blow landed late last year, when the FT published a report and company documents suggesting that profits and sales had been inflated at Wirecard outposts in Dubai and Ireland. Wirecard again denied the allegations. But an investigation by KPMG published in April found the company had not provided enough information to fully explain issues raised by the FT. Billions go missing The fall from grace accelerated on Thursday, when auditors at EY announced that they could not locate €1.9 billion ($2.1 billion) in cash that was supposed to be in Wirecard’s accounts. “We have information indicating that spurious or falsified balance confirmations have been provided in relation to these accounts,” the accountancy firm said in a statement. Braun suggested Wirecard may itself be the victim of fraud. “It cannot be ruled out that Wirecard has become the aggrieved party in a case of fraud of considerable proportions,” Braun said in a video statement released before his resignation. In a resignation letter published by the company, Braun said he did not want to burden Wirecard. “The confidence of the capital market in the company I have been managing for 18 years has been deeply shaken,” Braun wrote in the letter. “With my decision, I respect the fact that responsibility for all business transactions lies with the CEO.” The company is now scrambling to find the money to keep creditors at bay. According to Wirecard, €2 billion ($2.2 billion) in loans to the company may be called in on Friday if auditors don’t sign off on its results. Wirecard said in a statement Friday that it is “in constructive discussions with its lending banks with regard to the continuation of the credit lines and the further business relationship.” In Germany, the scandal at Wirecard is raising questions about the Federal Financial Supervisory Authority, or BaFin. “BaFin was a spectator for far too long and instead accused FT journalists of market manipulation,” Fabio De Masi, a member of the German parliament, said on Twitter. “Now quite a few small investors are suffering. BaFin has to change radically its approach to regulation.” The regulator said Friday that it is actively investigating Wirecard. “We are examining Wirecard’s disclosure from yesterday as part of our investigation into whether the company violated rules against market manipulation,” BaFin said in a statement.