For users of DAZ History Manager
For those who have been using the DAZ History Manager:
"Check Cart for Duplicates" has unfortunately shown not to be completely reliable because of inconsistency between some product names in the history and the product pages/cart. If you have used it for one or more purchases, it's strongly recommended that you check these purchases manually using the Search function, by doing a separate search on each word in the product names from the product pages. This should find any possible matches.
Sorry for the inconvenience. :( Hope to have a fix ready soon...