What mistake did Tan Chengwei, the headmaster of Zhongyuan No.1 Middle School in Heshan, Guangdong Province make?

There is nothing wrong with Tan, the headmaster of Zhongyuan No.1 Middle School in Heshan, Guangdong. According to relevant information, retired teacher Tan has been the principal of Heshan No.1 Middle School for a long time. He has been an excellent teacher in China and an excellent propagandist in Heshan for more than 30 years. Tan Chengwei, a retired teacher in Yuqiao Village, Shaping Street, Heshan City, has been the principal of Heshan No.1 Middle School for a long time and has been an excellent teacher in China for more than 30 years. After retiring from 20 17, President Tan loves propaganda culture and creative writing, has played aerial photography and has rich experience in drone control and aerial photography. He is a well-known volunteer aerial photographer in Chuangwen Road, and often takes aerial photos of various large-scale civilization creation activities in Heshan City. Providing video material and public micro-signal "Heshan Release" for the special column of Heshan Radio and Television Station "Wonderful Heshan", 20 18 was awarded as an excellent propagandist in Heshan City.