I have the same problem with a Mini 2nd gen. I created a new merchant right before and associated it with the device, but the devkit cannot overcome the last step. Internet connection of the device is also fine. I tried associating again after the code expired, but the same happened again. Currently this devkit is useless for me :( EDIT: I tried again with another merchant (which I used previously) and it worked. Maybe the problem occurs only with brandnew merchants.
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