The settings you have look fine, it looks like there is a problem with the abbreviation you are using for this local as well, you should try using BC.
I'm not sure where you are getting the full names for these locations from, the checkout forms list the Canadian provinces by name, but for the values it has all of the correct two character abbreviations. If you use this select list for the billing and shipping values then you should not have this problem. Please take a look at this and test the other values for these provinces to see if you get a better result.
