Parcel stuck at Beijing.Tracking number is RB161880345CN.

Hi. Could you perhaps help with this. I ordered a parcel from e-bay and has been going between Guangzhou and Beijing a few times and now it is stuck at Beijing since 27 July. I tried to contact the seller, but she is ignoring my emails. Is there any way of finding out who the carrier is or why its stuck? Thanks for the time and help.