Why my screen lock on my Samsung galaxy note 5 not working?

[Android Central Question]

I lock my screen and it locks, but when i try to unlock it with password it unlocks, but it unlocks with anything i type.
I was first using PIN security, i thought the problem must PIN, then i changed to password security but no vain.
Where must the problem be?
I think the problem is in patch-update.
SECURITY SOFTWARE VERSION.
ASKS V1.4 Release 180122
SMR AUG-2018 Release 1
Android Security Patch level
August 1, 2018

 

[B. Diddy]

Welcome to Android Central! Are you certain this is a genuine Samsung product, and not a clone/knockoff device? Did you get it brand new from Samsung or a carrier?

Please register on this forum, which will allow you to engage in discussion more easily, as well as post images. https://forums.androidcentral.com/ask-question/409154-join-android-central-community.html

 

[dell laptop]

Yes, i am sure it's original phone and i have been using it since 2017, no complaints back then.
I figured out this issue yesterday, my little nephew was taking my phone to watch YouTube on it, he sneaked it so i didn't unlocked it for him.
Yesterday i asked my sister-in-law that whether she knows my phone password and she told me that its '123456', i was like what.
Then i unlocked it 123456 and then i tried some more and it actually worked.
Then i changed from PIN SECURITY TO PASSWORD SECURITY, but the problem still exists.

 

[B. Diddy]

Does this also happen in Safe Mode? https://www.t-mobile.com/support/de...xy-note5-n920t/safe-mode-samsung-galaxy-note5