So i just got this phone from overseas it's on 4.4.2 baseband version I9505XXUFNBH, I need to get it unlocked but when I put my sim card in it from a different carrier i don't see any options come up for me to enter a unlock code? So I'm wondering if it's already unlocked but still when I have my sim card in it i don't get any signal bars whatsoever, only that circle which is crossed out i see there so anyone have any idea what might be wrong please