It broke after one of the OS updates. Maybe it was the original Creators Update. Microsoft changed something and that didn't go well with Spotify's code and Spotify doesn't want to fix their **bleep**. Paradoxically, they recently announced a presence in Windows Store which implies an UWP app just cut down and not available on other platforms. I mean, why did they even bother? There's always that old way via the installers. Alternatively, if you already started doing that, why not go all the way to a complete UWP package? These days Spotify's decisions are baffling.
The "app", if you can call it that, on the store is just the desktop application in a .appx wrapper. Not much point to it as you can still download the desktop application from their website anyway.
I'm switching to Deezer on not just Windows 10 and my Lumia 950XL but on my Nexus 5X as well. So well done Spotify for losing a potential customer, if you can't support me as a Windows 10 Mobile user then I can't support you as an Android user.
My wife and i are having this error too. I dont use WhatsApp. What other apps might be causing issues? I use Grover Pro for podcasts, Groove for my own music, Twitter, and other Win 10 built in mobile apps.