after software update

[Mchls]

everytime that i am going to restart my phone there's error message showing " serious issue update install" when i tap it, it will goes back on the settings in software update page that my device is up to date . 

try already some basic troubeshooting steps with customer support but still the same. 

[BandOfBrothers]

In regards to the software installation you completed was this via the phone's own software update section  @Mchls  ?

Try > Clear Cache Files from the phone's System Partition Section  > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too. 

You could try a Factory Reset as a last resort after backing up, but if this does not work then you may need to let Samsung have hands on via a Samsung Service Centre or Samsung Experience Store. 

If I can be of any further help then please don't hesitate. Take care.  😎