Having got it worked for me after reporting the issue to Azure support, and hearing that people are still having issues, I reported this back to them. They've suggested that people can create service requests on the Azure portal "as creating a request is without limitations for [them] to validate the issue":
At the bottom left of the Azure portal page, there's a button to create a "New support request". They got this working for me pretty quickly, 2-3 working days and it was sorted.
If they do this for enough people, hopefully they'll fix it for everyone. Anyone else try giving that a go? PS. In response to the above email, I have pointed out to them that there is already a Community Idea to support Revolut cards, and it's been open for over 6 months already.