Could you tell from the speaker’s tonal presentation that Loudness was actually off?

Which Sonos device(s) are you referring to and which Sonos App controller?

speaker is Move 2. I couldn’t tell that the Loudness was off. Same with bass and treble - I couldn’t detect any change. And when I turn off the loudness and check back later it has turned back on. 

 Sounds like the settings never made it to the Move 2.  Don’t know why.  Sonos needs to make it clear with some form of messaging that lets you know the Loudness did not take.  Then they need to explain why that might happen.

I inadvertently solved the issue. I signed out of the Sonos app then signed back in. Now the equalizer and Loudness work fine.