Hi there guys!

I've just bought used Galaxy Note. I've tried it while the guy, who sold it to, was still using it and it worked fine. When I bought it, he made factory settings reset. But when I try to use it with my sim card it doesn't recognize it at all. When I for instance want to register my samsung account it says: insert sim card. I've tried 3 different sim cards and none of it works. The phone is not locked. Also there is gray icon of sim card at the top of the screen (at least for me it looks like sim card). I've managed to enter my gmail account. Can anyone help me?


p.s.: this is my first android phone, so beginner mistakes are not excludet

Thanks guys!