Paid Subscription not switching members to different usergroup
 

From day 1, after members purchased a subscription and paid, it would switch them over to the appropriate user group.

Well, the past three days, each member who had purchased a subscription have told me that they have not been switched over after paying through pay pal. My pay pal account will show that they have paid but vbulletin is not switching them over. Any ideas why? Like I said it was working fine from day 1. Just some how something happened and it stopped.