TIJUANA, Mexico — The number of migrants waiting at the southern border in hopes of being seen for CBP One immigration appointments cancelled when President Trump was sworn into office has halved in the last day.

About 100 migrants remained camped out at the San Ysidro border checkpoint Tuesday, after about 200 had stubbornly refused to leave when the Trump administration shut down Biden’s Customs and Border Protection app that allowed hundreds of thousands of migrants to enter the country.

And some have even continued to arrive fully aware that their appointments are gone.

“We came to the border this morning in the hope they will keep our appointment, even though it was cancelled,” said 30-year-old Dania Rebeca Salgado Aleman, a Honduran mother who had an immigration meeting booked for 1 p.m. Tuesday.

Aleman travelled by foot to Mexico with her daughter in the hopes of finding treatment for the 9-year-old, and to escape crime that destroyed their livelihood in Honduras.

“It’s so upsetting to think we’ve come all this way for nothing, after suffering so much to get here,” she said. “The truth is we don’t know what we will do if we are not allowed into America.”

“We are adrift. We can’t go back to Honduras. I had a bicycle parts store, but I was extorted by gang members and lost everything.”

Others said they’d bet everything on their CBP One appointments, and simply have nowhere else to go.

“What am I going to do? I have no place to go,” said 38-year-old Martha Torres, who travelled from El Salvador for an immigration appointment that was scheduled for Wednesday.

“Why wouldn’t he at least honor the appointments already approved?” Torres said, explaining that her teenage kids are US citizens so she sent them across the border by themselves – and that she was desperately hoping to be reunited with them.

“My kids were sad but didn’t say anything, they just cried,” she said. “Why would Donald Trump do this?”

They were among scores of asylum seekers who had their long-awaited immigration appointments canceled at noon Monday when Trump took office and immediately halted the use of CBP One – which the Biden administration used to allow about 900,000 migrants to flow into the country during the last two years of the president’s term.

The app allowed more than 1,400 people daily to schedule appointments with immigration officials at US ports of entry, and then make their way into the States — meaning about 43,000 migrants per month were being given chances to enter the country through CBP One since it was introduced in January 2023.

Trump shut it down as one of several sweeping Day 1 acts to address the border crisis, which he declared a national emergency during his inaugural address.

Many saw their appointments vanish just minutes before they were scheduled after waiting months.

A young Cuban couple at the San Ysidro border checkpoint — Luis Miguel Alvarez, 22, and Adriana Lopez, 20 — had relocated to Mexico City after being persecuted by Cuba’s government, they said. 

The pair had been waiting to secure a CBP One appointment since they made the move in November 2023 and on Jan. 2 were finally given a time and date — for one hour into Trump’s second term as president.

“We found out our appointment was canceled at 9 a.m. this morning,” Alvarez told The Post Monday. “I am devastated that our appointment was canceled but we still have hope.”

The couple had intended to claim political asylum.

In Cuba, Lopez was studying robotic engineering, and Alvarez was studying nuclear engineering but was allegedly kicked out of his courses for his political beliefs. He said they couldn’t go back as Cuban police harassed them and that Mexico, their current home, was dangerous.

“We understand that the new president wants to defend his country and its borders but we are not criminals,” Alvarez said. “We want to study, work and be of help to the United States.”

Some migrants were filmed weeping on the Mexican side of the border after they saw that their long-awaited appointments had been canceled with the app’s closure.

Others, like 50-year-old Erica Ramirez, are refusing to leave until they get the appointment they were long promised.

“We have been waiting for the appointment for 11 months,” she told The Post after her 1 p.m. Monday appointment vanished. “We will keep waiting here until we get an appointment.”

She planned to spend the night at the border checkpoint with her son, daughter-in-law, and their 1-year-old and 4-month-old daughters.

“We will sleep on this very site,” she said. “The state where I am from, Guerrero, is very, very dangerous. There is a lot of violence.”

“My son is a builder and I am a cleaner,” she said.

“We are going to America for a better life, fleeing from crime and the fear we have in our own country.”