I would suggest you read @Anniepan's first post in this thread again:
https://www.fasttech.com/forums/shipping/t/3014287/?3014469

That indicates that FT has an ongoing inquiry with China Post and/or its carrier and they are awaiting a clarifying response.
From experience I know that these matters take time.

I am mentioning that because I recently had a shipment from FT that went AWAL.
No tracking records of it anywhere after 2 weeks.
I suspected that I might have got a faulty tracking ID and opened a ticket asking customer service to double check the tracking ID for that parcel.

After two days i got the following answer:
It's correct tracking number RP106428339SG.
Please click: https://t.17track.net/en#nums=RF721170565SG
Could you kindly give it a couple of days first? It should update soon.


Three days later I got another ticket message:
Carrier changed the tracking number before.
It's RF72117XXXXSG.
Sorry for issue we caused.


So apparently they had made an inquiry with the relevant carrier and gave me a disorienting answer before the carrier had answered them.
It might be something similar in your case.

By the time they confirmed the hickup my parcel was already stuck at my country's customs for one week.