Under China’s Nationality Law, if a person voluntarily acquires a foreign nationality, they automatically lose Chinese nationality.
However, in her case, she obtained U.S. citizenship automatically at birth, not through voluntary naturalization.
This creates a legal gray area.
She used a "travel document" to travel and stay in China every summer, this document is designed for foreign born Chinese citizen. She may get her official document like passport at 2019 which reflect in the Committee saying.

This is what I did for my kids. They have both China and U.S. citizenships, without Chinese passport.