Zacks Investment Research claims Twitter will struggle to convince advertisers to return to the platform, following the revelation that “up to 15%” of the platform’s users are bots.

A study released this month revealed that as many as 48 million Twitter accounts are bots.

“Jack Dorsey, CEO of Twitter Inc., is facing another problem in convincing advertisers to return to Twitter, as new research showed that up to 15% of Twitter’s 319 million users could be bots rather than human,” Zacks reported this week. “The research was conducted by University of Southern California and Indiana University. Researchers used more than 1,000 features to identify bot accounts on Twitter. It was estimated that between 9% and 15% of active Twitter accounts are bots.”

“The estimate of 15% is almost twice of Twitter’s own estimates. In Twitter’s Q4 earnings, the company reported up to 8.5% of accounts could be bots,” they continued. “The company’s performance and the bot scandal puts further pressure on Dorsey to step down as Twitter’s CEO.”

Twitter’s problem with bots has been a growing issue over the past few years, with some accounts, such as feminist commentator Anita Sarkeesian, being reported to have followers that are up to 55% fake.

The platform’s stock price has also been plummeting over the last five years, with one top equity research analyst branding Twitter as “toast” in December.

In February, it was reported that Twitter’s shares “crashed” following the release of the company’s fourth-quarter earnings report. According to analysts, the fact that Dorsey splits his time as CEO of both Twitter and Square is another negative for the company.

Charlie Nash is a reporter for Breitbart Tech. You can follow him on Twitter @MrNashington or like his page at Facebook.