What is the reason you cannot reload the app?

Can you confirm that you are trying to install the S2 app?  The Sub Mini only works with that version. https://support.sonos.com/en-gb/article/sonos-s2-compatibility

Hello, and thank you for the replies. Turns out that it was the stupid phone! After multiple restarts, cache clearings, etc. I finally persuaded the app to load, and from that point on it was relatively plain sailing, and we are up and running.

I just wish that people would devise systems that didn’t require a degree in computer science. Or a substantial slice of clairvoyance. “Go to menu X, click on item Y”. But what happens when item Y actually isn’t there? One then has to go off on a treasure hunt. Perhaps it’s a function of age (I’m 75) and I come from a time when one simply wired things together and they worked.

……..or exploded. ;-)

Not sure why your phone would not perform the basic function of updating an app.

Makes two of us! Personally, I put it down to natural talent on my part. I keep trying to convince my employer to make me a part of their IT team, because, if there’s a problem with a computer system, I will find it every single time.