Help me find a solution

-- HikaShop version -- : 2.4.0
-- Joomla version -- : 3.4.0
-- PHP version -- : 5.4.38

Hello to everyone.
Hikashop is a great component. I used it now and i will do it in the future. I have a serious problem with my e-shop. I find a freelancer to help me with the ckeckout process to make some custom stuff because i dont know php. The customer in the checkout process has three choices, create an account, be as a guest, login with his Tax Registration Number. After the update to hikashop 3.4.0 this doesn't work. The eshop is online and customers has problems to confirm their buys. May you can find a solution or solve the problem?It isnt fair everytime I update the hikashop pay someone to help me fix this kind of problems.
Thanks in advance

Hello,

After the update to hikashop 3.4.0 this doesn't work. The eshop is online and customers has problems to confirm their buys.