When Noknoi attended high school in northern Thailand, she dreaded roll call every morning, when the teacher would call her first name and then say "nahm somut", or "made up name" - the standard suffix for stateless children.
Thai students would snigger, and Noknoi and other so-called stateless children were often teased by students and teachers alike, she said.
"Being stateless meant having no identity," she said.
"We were reminded of that every day, with even our names taken away - we were nobody," she said.
Noknoi, who asked that her surname be withheld due to the sensitivity of the topic, was born in a Thai village near the border with Myanmar.
Her four siblings were also born in Thailand. But because their parents were from Myanmar, they were not recognized as Thai citizens until a few months ago - nearly three years after Noknoi applied for citizenship for all five of them.
They were among the 487,000 stateless persons registered with the Thai government this year, according to the United Nations refugee agency (UNHCR).
Activists say the actual number may be more than three million.
Stateless people include indigenous hill dwellers and children of migrants who were born in Thailand. They have limited work options and are barred from voting, traveling outside their province, and from buying land.
They are worse off than the tens of thousands of refugees from Myanmar who live in camps in Thailand where they are registered with the UNHCR and served by aid agencies, activists and analysts say.
"In a school uniform, stateless children can appear and feel undifferentiated to Thai citizen students," said Janepicha Cheva-Isarakul at the Victoria University of Wellington.
"It is only around the teenage years that they become more aware of the limitations of their status and start learning about possible legal pathways to becoming Thai citizens. But it is a complex system of unevenly applied regulations," she said.
Many stateless people in Thailand are from areas where boundaries between its four neighboring countries have changed, or who have crossed the border for work or a better life.
About 100,000 refugees from Myanmar remain in camps along the border in Thailand, according to the UNHCR, after fleeing six decades of war between Myanmar's military and ethnic armed groups.
"There are some refugees who have lived in a camp all their lives. They have no connection to Myanmar and nothing to go back to because they have lost their homes and land," said Matcha Phorn-in, an activist who works with stateless people.
"Of those who were born here, few have birth certificates, land titles or other documentation for Thai citizenship, so they remain in limbo," she told the Thomson Reuters Foundation.
In recent years, Thailand has amended its Nationality Act to make it easier for displaced Thais to get citizenship. But it is not a signatory to the 1951 Refugee Convention, which spells out legal obligations to refugees.
Since 2005, Thailand has given all stateless persons access to basic education and health care, and pledged to develop a screening system to curb trafficking, which is a major risk.
State hospitals now issue birth certificates to all children born in Thailand, and there are more job options for stateless people who were once limited to 27 low-skilled occupations.
Thailand's military government, which took power in 2014, has committed to "zero statelessness" by 2024.
But applying for citizenship remains a "challenging and complex" process, said Janepicha, who has researched stateless people in northern Thailand.
While Thailand recognizes citizenship by descent and by territorial birth, applicants must present birth certificates, their parents' identity papers, and get the village head to attest they are a member of the community.
"A process that relies heavily on documents as absolute proof of identity risks placing blame on the people for not having the documents, rather than questioning why they did not have the documents to begin with," Janepicha said.
The documentation is comparable to that required in other countries, and applications are considered "on a case-by-case basis", said Venus Srisuk, director of the Bureau of Registration Administration.
Thailand has given about 100,000 people citizenship since 2008, making it the regional leader, according to UNHCR.
Noknoi applied for citizenship about three years ago, when she started college.
It took her two months to get birth certificates for herself and her siblings, and several trips to the village and district offices to complete paperwork that ran into nearly 50 pages for each, she said.
"I could only do it because I was educated, was aware of my rights, and had help. Most others are not in that position," she told the Thomson Reuters Foundation in Mae La Noi town.
"At times, I thought I would die before we got citizenship.
Even now, I am afraid it can be taken from me," she said.
Changes in the citizenship laws in 2016 opened up a path for some 80,000 stateless persons, with alternate requirements such as loyalty to the king, good conduct and educational achievement.
But the conditions are subjective and based on "deservedness" rather than a fundamental right, said Matcha.
The issue came into focus after the dramatic rescue in July of 12 boys and their soccer coach from a flooded cave in northern Thailand.
Three of the boys, as well as their 25-year-old coach, were stateless, though they were born in Thailand.
Just weeks later, they were granted citizenship after officials fast-tracked their applications.
"Congratulations to those who get citizenship by being deserving, but it is a double standard," said Matcha, the activist. "Should everyone have to be rescued from a cave to be found deserving?"