issue with points system not updated member level

I am having an issue where when members reach a certain points threshold, their member level is not being updated properly.  I have the Update membership level when member reaches the points level set to go to the level when they reach it, but when they do, they are not upgraded.  For example, they start out as standard with minimal permissions...once they reach 25 points they reach the bronze level and thus should have their membership level upgraded to bronze, but for some reason this is not happening.