Hi, do I need a transit visa? My flight from Seattle to Jakarta and will transit 2 hours in Shenzhen

Hi, I hold Indonesian passport and onward ticket to Jakarta. My flight from Seattle to Jakarta and will transit 2 hours in Shenzhen, then transit again in Xiamen during 19 hours before leaving xiamen to Jakarta (I also have return ticket from Jakarta-Seattle)

Thank you very much for your help


Best regards,
Kamal