Can't copy music files from windows laptop for sonos to play

I’m new to this. Bought a mycloud home (4tb) yesterday, got the app on my phone and it uploaded all my photos easily. My main reason for purchasing though was to back up my music (and photos libraries) from my windows 10 laptop with a view to playing them through my sonos system. I bought the mycloud home as sonos was compatible with it and I have already set up the sonos to recognise the mycloud service.
Anyway i log into the my mycloud home webpage and try to add my music folder but it won’t copy any folders. you drag and drop and nothing happens unless i do it by individual files, which would be a very slow and inefficient way of doing it. To try and sort this i used file explorer on my laptop, found the mycloud in network and copied all my music into the public folder, which took over 2 hours. All my music successfully copied and it can be seen on file explorer. I was hoping that by doing this i could access them using the app on my phone and the sonos system, but they are still not showing on the webpage, app or sonos system.
Can someone please help me either copying files from my laptop (i can’t copy photos from there either) or getting the app to recognise the files that i can see on file explorer.

Thanks

Steve

@stevee4

My Cloud Home (wd.com)

that really isn’t helpful, the first thing it tells me is to update the firmware and that linked to a page in japanese. Could you at least point to which page i need to look at?

Oddly the app is now recognising my music folders but they all look empty. Do i just need to wait and they will be populated in time?