“The address of your business does not match any of the known counties for your country “. I live in the UK, business address is here so what’s the problem?
We can do some browser troubleshooting steps to check if this error is caused by a full cache. By the way, which part of QuickBooks are you getting this error? Are setting up your VAT information?
You can log in to QuickBooks in private window. This disables your cache from saving new data, and it's a good initial step to check browser issues. If you can save your company address, you can go back to your regular browser and clear its cache. If you can't please try other browsers to isolate the case.