Bought a new DJI drone which doesnt work, took it back and was advised that it is being shipped to their technical department for further investigations - How are the internal processes of istore my problem? There is the exact same model on dispaly, i was

Bought a new DJI drone which doesnt work, took it back and was advised that it is being shipped to their technical department for further investigations - How are the internal processes of istore my problem? There is the exact same model on dispaly, i was told that they cannot swop out a replacement or refund my money. Why is a new purchase handled as a warranty claim? Terrbile!!! Stay away from istore!!!