Incorrect total amount when adding up event tickets

When registering for an event, the addition of the total goes wrong.I have added ticket types in which prices for children and infants have been added.
When I want to order an event ticket for 2 adults, 1 child and 1 baby. (ticket information)
I click on register and enter 2 adults, 1 child and 1 infant, but then I see in the total amount to be paid that 3 adults are calculated instead of 2 that I enter.
Total amount is 3,960,000 but it should be 2,660,000. (payment information)

This means that you actually only have to enter the extra cards and not your own.
However, this is confusing, how can this be solved, so that you just enter the number of cards you want ?

Thanks,Edgar