Quite a common scam... send a really basic cheap item so that you sign for the parcel then only discover when you open it its a worthless item . Happened to us, we contacted the seller who at least answered but then asked us for codes on the label and kept saying it was an invalid code so wouldnt refund, then eventually they offered 20% off then 30%. Eventually we claimed via credit card and got refunded.
Moral... if an offer looks to good and its an overseas supplier (especially China as ours was- big mistake) you havent heard of then look elswhere