More than 900 young immigrants applying for a renewal of temporary work permits had their applications rejected because of mail problems, a number far greater than immigration lawyers had thought earlier this month.

The United States Citizenship and Immigration Services acknowledged the significant impact on Thursday, as it released information on how those who had been turned down could submit new applications.

The immigrants were trying to renew their work permits under the program known as Deferred Action for Childhood Arrivals, or DACA, which allowed nearly 800,000 immigrants who were brought to the country illegally as children to work and go to school in the United States without fear of deportation.

On Sept. 5, the Trump administration canceled the program, but said those whose permits were expiring before March 5, 2018, could renew their application by Oct. 5 for a two-year period.