I had a case of a defective HP Prime. It was one of the first ones, and it stopped working, no matter what. I decided to call the guarantee, since I was not able to revive it. Fortunately, I had registered mine in HP’s website. Make sure you do the same next time you get a new calculator.
By the way, they’ll check if yours is a “grey import” or a legitimate “EAME” version. The guarantee supports you in your part of the world. There is nothing wrong with buying overseas (while you may want to take into account that your local seller charges VAT and the import does not - a full 21% difference in our case, higher in Scandinavian countries), but HP does not actively support it.
I then received yesterday a DHL box with a new calculator. It comes wrapped in bubble plastic. I expected it to be part of a new production lot (either a B or C revision, as they are being called lately), but it isn’t: it’s the exact same machine that I had (but working properly)
Thank you, HP, anyway. Guarantee honored!