I have several spreadsheets which I am trying to incorporate into 1 map and have been generally successful. All lines in the sheets have United Kingdom as the country. Most postcodes are being mapped correctly but some are being mapped to Kingdom, Illinois. I can't see any difference in the data for those lines which are being mapped incorectly. Can anyone help?
We've been experiencing some odd geocoding issues along these lines lately and are looking into a solution.
In the mean time, here's a workaround...
Recreate your map and, in step 2 of the map creation process please assign your fields as outlined in the screen shot below. This will put the postal code into the geocoding string before the city and should yield the desired results.