1. I suspect your parcel was never able to pass the Export Customs scan:
China Post Register Air Mail Tracking System

Parcel No.RK459474673CN tracking result
2016-09-19 08:48:47.0 盐城city parcel process center received
2016-09-19 11:39:56.0 盐城city parcel process center customs scan
2016-09-19 12:33:44.0 leaving 盐城city parcel process center ，next station 盐城center
2016-09-20 13:55:32.0 Nanjing Transit Station export security scan
2016-09-20 14:32:14.0 Nanjing Transit Station arrive customs
2016-09-20 14:33:38.0 Nanjing Transit Station export customs scan (domestic transit )
2016-10-18 10:31:02.0 Nanjing Transit Station arrive customs
2016-10-18 11:00:07.0 Nanjing Transit Station export customs scan (domestic transit )

2. You might want to look at this:

What is the status of “Export Customs Scan” ? How long it will take?

China Post Forbidden Item List

3. You should contact seller and tell him you have not receive your parcel and try to have an arrangement with him. Or if you can open a dispute for non reception of parcel.

Thanks.