Read the information about the transaction by pressing the info button - blue i button.
You can also take a look at the note 535043.
This is perfectly normal to happen in a system, it's just an inconsistency which happens
in some reasons mostly technical, doesn't have to do anything with your functional settings,
so don't worry about it, just check LX23 in test mode from time to time, you can see all the
inconsistencies there, and periodically fix them (post).