Elon Musk said on Saturday that Twitter will temporarily limit the number of posts users can read per day to address concerns over data scraping, just hours after thousands of users reported widespread problems using the site.

Many of those users reported that they were getting an error message that they had “exceeded” their “rate limit,” suggesting that they had violated Twitter’s rules and downloaded and viewed too many tweets.

Mr. Musk, who said on Friday that “several hundred organizations” were taking Twitter’s data in a process called scraping and that “it was affecting the real user experience,” did not say how long the limits would last or what could prompt him to lift the restriction.

He originally said that verified accounts would be limited to reading 6,000 posts per day, unverified accounts to 600 posts and new unverified accounts to 300 posts.

About two hours later, he bumped those limits to 8,000 for verified, 800 for unverified and 400 for new unverified — before raising them again early Saturday evening to 10,000, 1,000 and 500.

“Rate limited due to reading all the posts about rate limits,” Mr. Musk said on Twitter.

The billionaire has been vocal about his dislike for organizations that scrape Twitter and use tweets for research or to train artificial intelligence programs.

But the change on Saturday prompted frustration on the platform among some users, with many questioning why their online activity would be so drastically curtailed.

The phrase “rate limit exceeded” trended on Twitter, spurring memes on the site about people who were inconvenienced by the new policy. Downdetector, a website that tracks reports of malfunctions on several websites, showed that user reports of Twitter problems surged on Saturday.

Other users had more pragmatic concerns, including how the daily limits could affect the way people monitor severe weather on the platform, which often involves scrolling through dozens of updates, alerts and warnings.

“This Twitter change today is a total dumpster fire,” James Spann, a meteorologist in Alabama, said on Twitter. “Unless something changes, this platform is now pretty much useless for those of us in the weather enterprise.”

A email to Twitter’s communications department seeking comment was returned with a poop emoji.

Since Mr. Musk’s takeover in October and his moves to eliminate more than 75 percent of the company’s work force, Twitter has become less stable, with features or the whole site sometimes going down without explanation.

On Saturday, engineers in the company raced to diagnose the problem in private Slack channels, according to two employees. Those people said that Twitter salespeople asked what they should tell their advertising clients as they realized that some ads were not being displayed on the social network.

Twitter’s U.S. advertising revenue for the five weeks from April 1 to the first week of May was $88 million, down 59 percent from a year earlier, according to an internal presentation obtained by The New York Times.

The company has regularly fallen short of its U.S. weekly sales projections, sometimes by as much as 30 percent, the document said.

The frenetic changes at Twitter have continued to motivate some users to try other similar social media sites, such as Mastodon, which aims to be a “viable alternative to Twitter,” and Bluesky, a social network that offers many of the same core features that Twitter does.

Bluesky is currently invitation-only, but on Saturday the company’s name was trending on Twitter.

One Twitter user appeared to have had enough on Saturday, writing, “I need a Bluesky code so bad bro.”