Why can't I redownload my purchased album on iTunes?

Some time ago I purchased an album via iTunes on my iPhone and it’s been fine for a few years. Today however I noticed that the name of the album had changed to something incorrect. With no means to update this on my phone, I figured I’d be best off deleting the album and simply redownloading it, as I’ve done in the past.

Sadly, that doesn’t now seem to be an option; the album exists in iTunes, and it’s flagged as ‘Purchased’, but I can’t click the button to redownload.

Any ideas? Im pretty sure I’m not doing anything wrong, and am pretty annoyed to have lost access to some much-loved music.