1. Your tracking number is a valid tracking number. Sometimes it may take up to 10 days for a parcel to register into China Post system.

2. If after 10 days you can not track your parcel, then just contact seller and ask him if he did physically mail the parcel.

3. This is what I get when I track your parcel:
Item is not found at this moment, If necessary, please verify with the package sender and check back later.

Hope this help.

1. Your parcel is active now:
Number: LT568749970CN
Package Status: In Transit
Destination Country: United States
2016-12-15 00:45 Origin Post is Preparing Shipment, We have received notice that the originating post is preparing to dispatch this mail piece.
2016-12-15 00:45 CHINA, SHENZHEN EMS, Processed Through Facility
2016-12-14 20:11 CHINA, Acceptance
Origin Country: China
2016-12-15 03:44 Shenzhen, left Shenzhen to Shenzhen postal courier company (Hong Kong) business unit
2016-12-15 03:44 Shenzhen, Shenzhen City, leaving to New York's Kennedy airport
2016-12-14 20:11 Shenzhen, China postal express and logistics Corporation, Shenzhen Baoan branch business package has been received (the embrace cast member name: Lu Zhicheng, Tel: 23321292)
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Hope this help.