get a new domain price question

I am trying to add a new domain name to my account.   I understand the $24/year +$5 set up fee but when I go to submit page is shows a total of $48 +$10.    Why?    I see no reference to 2 yrs nor I did not select any other extensions.      I need this new domain but I do not want to overpay for it.     any explanations would be helpful