It’s like the process breaks down sometimes. It shouldn’t take more than 24-48 hours I believe. I would keep contacting Sonos Sales. 
 

I’ve called them a few times now, and each time I get a promise that it’ll be sorted, but then nothing.  It’s so frustrating to deal with!

I’m not gonna say this is a common issue, but experiences like yours do get posted. Also keep watch for the refund cause you may need to call and remind them about that as well  

All I can do is repeatedly call it seems, and get fobbed off with false positivity.  It’s a pretty frustrating experience, for something that should be quite straightforward to resolve.

Yeah I would imagine that you have better things to do with your time. This is unfortunate and it sucks. 

Just curious to know if you ever received your shipping label.  I also have contacted Sonos several times and waited to receive the shipping label via email while I waited on the phone.  Person tried it several times and said to give it 24-48hrs to appear in email.  I of course have checked spam and trash etc.  Product I am waiting to return is the Roam 1 which stopped working and had a long discussion with support with testing over the phone - he said he would send me a new Roam even though mine was out of warranty which I though was great, but no return label which must be used to return the broken Roam first to Sonos.  Seems like this is one of their tricks to make customers happy then go away.  

Did you ever get yours???

Thanks, Anne