Immigration courts reopened to a scene of "chaos" this week after being closed for more than a month due to the partial government shutdown. Some immigration attorneys say it could take weeks for the courts to return to normal.

Nearly 90,000 immigration hearings were canceled because of the shutdown, according to Syracuse University's Transactional Records Access Clearinghouse. Hundreds of thousands of documents didn't get filed during the closure, leaving a mountain of work for court administrators to wade through.

CBS News heard from 12 immigration attorneys from around the country who described their experiences following the shutdown.

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"Court is total chaos," said Alan Pollock, a New Jersey-based immigration attorney, in an email to CBS News. At Pollock's court in Newark, judges and government attorneys — those who argue against a migrant's case — didn't have time to organize the files they needed. All hearings on Monday at Newark ended up being adjourned and slated to be rescheduled, Pollock said.

In Los Angeles, every final decision hearing — or master hearing, as it's technically called — was cancelled , according to Ashley Tabaddor, the president of the National Association of Immigration Judges and a Los Angeles-based immigration attorney. In Miami, some judges just didn't show up, said Sui Chung, a Miami-based attorney, who said she heard similar stories from attorneys in other cities.

The immigration court system, which is overseen by the Department of Justice, handles a range of cases involving non-citizens, including issuing green cards and ruling on asylum claims. The courts also issue temporary Social Security cards — needed for work permits and driver's licenses — making many hearings intensely important for immigrants.

As late as Sunday morning, many attorneys and immigrants weren't sure whether their hearings scheduled for Monday were still happening, said Brian Casson, a Virginia-based immigration attorney.

Some attorneys prematurely notified their clients that courts would remain closed, forcing some immigrants to rush to court. The 1-800-number that provides status updates on cases was down all day Monday, said Chung.

"There was a lot of misinformation and rumors circulating all weekend," said Casson.

For many migrants, attending a hearing can be an expensive, time-consuming affair, Casson said. In Arlington, Virginia, some need to travel for two days via public transportation to make their court appearances.

Arlington's immigration court was a scene of "complete chaos" on Monday, according to Casson. His hearing on Monday was nearly two hours late. On Tuesday morning, the scene was still "particularly crazy," he said.

The backlog of cases is more than 800,000 and immigration judges have full dockets until 2021 and 2022. Attorneys aren't sure when their cases will be rescheduled, and many have assumed it could take years.

One of Casson's clients, a family of four, had a hearing cancelled during the shutdown. The family had been targeted by a gang in Central America after a family member became a police informant. The family is seeking asylum, and their hearing has been rescheduled for June 2019. It's a master calendar hearing — a very brief hearing to schedule a more significant hearing. They've been waiting for two years to see a judge.

None of Casson's final immigration hearings, which typically take between four and six hours, have been rescheduled yet.

If a deal isn't made between Republicans and Democrats over border wall funding by February 15, the government — and immigration courts — could shut down again.

"I don't know how they could handle another shutdown," Casson said. "They're barely, barely handling this one."

Read more CBS News immigration coverage:

The country's busiest border crossing will allow 20 people to claim asylum a day. They used to take up to 100

These Central Americans have a second chance at asylum after being "unlawfully" deported. First ICE needs to bring them back

Every congressperson along southern border opposes border wall funding