Buttons not working after recent update

[Harvinio]

After installjngvthe latest security update on my A5 2017, the app & back buttons no longer work.  Any ideas why & how to fix this?

[MohammedSijah]

Are the buttons not working or not appearing?

[Harvinio]

Both. The app button in the left & the back button on the right don't function on any app, that do nowhere light up briefly when the phone display turns on after being in power saving mode.