Yes, my app is for the UK - check what your url is when you log into your ConnectedDrive website - you might need to amend my code to address the correct servers as I believe they authenticate separately.
I think that if you’re in the US, you’ll need to change bmw-connecteddrive.co.uk for connecteddrive.bmwusa.com.
Also, check your logs - does the smart app report getting a token? you should get a debug line with a token and expiry before it attempt to collect your car details.