[HeardIt]

because i want to resell it, otherwise i would have sign it (and in addiction there is the sign of my doorman, i don't want to involve him)

So if you resell it then you don’t even have any evidence of having it. Now if you return it, it’s going to be blatantly obvious you tried to SE it

i would like to avoid if the buyer make a warranty claim and they deny it because the serial it's connected with a SE/stolen card

So I’ll ask again. Why did you do it in the first place?