India Post — package stuck at mumbai foreign post office

Address:

500032

Hi,
My package got stuck at MUMBAI FOREIGN POST OFFICE (Custom Hold), and the tracking number for this parcel is "RG[protected]BE". I bought this from www.gearbest.com website, and the international parcels usually will reach in 10-15 days. But i ordered this on November 11th, but it got stuck at Mumbai customs with the reason "Retention Reason : Retained by customs for unspecified reason". Now don't know the parcel state. And me (or) the gearbest.com did not received the package.
Kindly trace the parcel & deliver to me asap