Elementary school children play outside their classrooms as mount Sinabung volcano spews thick volcanic ash in the background on February 10, 2017 in Karo, Indonesia. Mount Sinabung is one of the most active volcanoes in Indonesia and last erupted in May 2016, killing seven people. (Photo by Albert Damanik/Barcroft Images)

Terashima Takeshi and Akaishi Kazuya of Japan block a shot from Indonesia during day one of the ISTAF Super Series at Palembang Sport Convention Center on February 23, 2012 in Palembang, Sumatra, Indonesia. (Photo by Nicky Loh/Getty Images for UFA Sports)

Residents with faces covered in ash ride on a motorcycle as Mount Sinabung volcano erupts, in Sukandebi village in Karo Regency, Indonesia's North Sumatra province, Indonesia June 13, 2015, in this photo taken by Antara Foto. (Photo by Rony Muharrman/Reuters/Antara Foto)

A woman worker prepares her stall at Tanah Abang textile market in Jakarta, Indonesia January 11, 2017. (Photo by Fatima El-Kareem/Reuters)

A Rohingya migrant who arrived in Indonesia by boat cries while speaking on a mobile phone with a relative in Malaysia, at a temporary shelter in Kuala Langsa in Indonesia's Aceh Province May 16, 2015. Nearly 800 migrants were brought ashore in Indonesia on Friday, but other vessels crammed with them were sent back to sea despite a United Nations call to rescue thousands adrift in Southeast Asian waters with dwindling food and water. Thousands of Rohingya Muslims fleeing Myanmar and Bangladesh are stranded on boats as regional governments block them from landing. (Photo by Roni Bintang/Reuters)

Sunset at Walakiri Beach, Sumba in East Nusantenggara, Indonesia in 2019. (Photo by Aries Hendrick Apriyanto/Rex Features/Shutterstock)

PALEMBANG, SUMATRA, INDONESIA - NOVEMBER 14: Fitriyani Fitriyani (L) of Indonesia and Janice Ng (R) of Singapore compete in the Sport Climbing Womens Speed Track Finals on day four of the 2011 Southeast Asian Games at Jakabaring Sports Complex on November 14, 2011 in Palembang, Sumatra, Indonesia. (Photo by Matt King/Getty Images)

A Rohingya migrant woman, who arrived in Indonesia by boat, carries a bottle of drinking water inside a temporary compound for refugees in Kuala Cangkoi village in Lhoksukon, Indonesia's Aceh Province May 17, 2015. (Photo by Reuters/Beawiharta)