I very strongly suspect you've bought a chinese fake that's had a bit of jiggery-pokery done to the drive's internals to make it appear to be 2Tb while in fact being perhaps only 16Gb or less.
I'd be very interested to hear the outcome, though I'm pretty sure I already know what it will be.
Given that a Kingston 1Tb flash drive from CCL Computers (a reputable & very competitively priced retailer) sells for £114 I'd be very surprised if you haven't been "sold a pup".
Kingston DataTraveler Max 1TB USB 3.1 Flash Drive, Mfg Code: DTMAX/1TB
www.cclonline.com