[mothered]

As mentioned, the never arrived or empty box method will suffice.

In terms of the latter (empty box), what's the size and weight of the drone?

the GLS tracking give me these box values:
Weight: 2.0 kg Volume: 3.0

why?

Items are weighed on consignment, hence If you're using the empty box method, you must justify the weight during transit.

Moreover, If the size of the Item Is too large to assume It was stolen, the method Is deemed futile.