In the latest version of the Free plugin there is a strange quirk in the display and registration of ticket prices and reserved seats. It repeats the first item in the ticket list again and displays it at the bottom of the ticket list. It also adds one ticket of that particular ticket to the total, which is very confusing and unwanted of course.
An example always explains it best:
You can see that at the bottom it says "€10" and Spaces: 1 with a dropdown. I don't think that's the total price of all the tickets (would be nice to have that auto updated while user selects tickets) and the Spaces choice is the one from the "En nog een" event. I made sure I have a vanilla EM install.
When I send in the form without changing anything, I get 1 standard ticket and 1 "En nog een" ticket:
This bug doesn't seem to appear in the Pro version, of which I have a demo account: