It looks like your merge isn't matching the rows as you expect.
I would try to investigate if there are "invisible" differences in the columnar values:
Canada
(with an appended space) will not match to Canada
for example. To check for this, go into the table you are merging and select to Trim
the key column.
In the table you are merging into, do the same Trim
operation for the key column.
Edit: Another option is to apply fuzzy matching to the merging process and to limit the amount of fuzzyness by setting maximum number of matches per row and adjusting the similarity threshold up from 0.80 to something closer to the maximum 1.00 (= exact matching).