Volume buttons do not affect alerts volume

[natimishali]

I have iPhone 6s Plus.
Since iOS 10.3.1 it seems that the volume buttons (or settings) do not affect
alerts volume (like send message sound, keyboard click sound, etc.) but only the ringer volume.
Anyone?
Reset did not help.

 

[Tartarus]

In Settings > Sounds & Haptics enable 'Change with Buttons' option.
This will let you increase / decrease the ringer and alerts volume with the buttons.