Login and registration error

-- HikaShop version -- :2.2.0
-- Joomla version -- : 2.5.14


We have a problem with login and registration:

Shop is set to simple registration, because we have files to download.
When we purchase a product, we fill out Email-Name-Phonenumber, and can pay - all that is ok.....BUT

when the same user later on wants to make a new order and purchase another product, it says that the e-mail exists and cant be used ?????

Please advise how to fix this..

regards
Bison

That's normal. The simplified registration means that the user registered. A user cannot register more than once with the same email address on a joomla website. So he just have to login with the login form instead of registering with the password he received by email after his registration.