To me it looks like your code should work just fine. It is going to return all columns that do not start with a character between A-Z, which as I understand, is your desired output.
If you more explicitly want to select columns that start with a one digit numeral followed by a full stop, this should work:
dplyr::select(yourData,matches("^[0-9]\\."))
Does that answer your question? Otherwise, you could consider using a reprex to show what you've got and why you'd need to modify your code.