Six months ago I won the lottery — the H-1B visa processing lottery for skilled foreign workers. I called my thrilled parents and celebrated with friends. I’m from northeastern China and have an M.B.A. from Stanford, and was planning to stay in Silicon Valley to help start a company based on a promising new technology to improve the use of data. I was overjoyed because, historically, being selected in the lottery was a near guarantee that an applicant could remain in this country at least three more years.

But at the end of July, I received the dreaded Request for Further Evidence from immigration authorities. I provided the extra information that United States Citizenship and Immigration Services asked for. In September, I got another request. I complied again. Finally, on Oct. 11, half a year after my celebration, I learned I had been denied a visa.

After earning law degrees in China and at Oxford, after having worked in Hong Kong as a lawyer at a top international firm, after coming to United States three years ago for an M.B.A. and graduating and joining a start-up, I was given just 60 days to leave the country. I have 17 days left.

In the past, it was fairly safe to assume that once you were selected in the lottery, your H-1B petition would be accepted by immigration officials. In 2016, this happened about 87 percent of the time. But things began to change in April when the Department of Homeland Security and the Department of Justice announced measures to increase scrutiny of the highly skilled applicants who use the H-1B program, and President Trump signed an executive order calling for federal agencies to suggest reforms to the program.