Could this be the same issue as the other two tickets, e.g. do you have another item that's not configured?
With access from the other ticket I can upload the latest development version (as it's unlikely I'll be making any database changes) so it might get fixed that way.
If you're curious, the reason why it occurs is that XF caches the item handler, which takes on the configuration of the first purchase from that handler. It's two lines of code to change to disable that cache.