Search The phone for an update! I've read/saw many ppl mention that a software update from Samsung fixed those issues.I have to say that this fingerprint reader sucks. I can barely get it working and may end up returning the phone over this. They should have left it the way it was because it is really bad.
If you have the unlocked version threre is no update yet. ?Having the same issues with the fingerprint sensor. Checked for an update almost as soon as I opened the box, but it indicates it's up-to-date so now I'm clueless. I'm continuing to play with it, but if I can't get some improvement it's going back.