System Issue

[Klaus]

As soon as phone locked, not able to unlock it after 5-6 attempts. Sometime its stuck with lockscreen and sometime its stuck with black screen. This issue comes after updating the phone One UI to 4.1

[cs_member8]

Dear Samsung Member,

Greetings from Samsung Customer Support! 
  
We acknowledge your query and apologize for the same. To resolve your device hanging issue please visit this link: https://www.samsung.com/in/support/mobile-devices/how-to-restart-the-device-when-freezed-or-hanged/

In case the issue still occurs. Please register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Error report/Ask questions).

Thank you for writing to Samsung.

Warm Regards,
Samsung Customer Support

[Klaus]

I've tried all things still same issue. After sometime I've done hard reset it fixed the issue.