[TYPO3-shop] Order confirmation email not sent to customer

[dana.novotna at ekodomov.cz]

Hello,
 
I have Typo3 v.3.8.1. and I have installed tt_products 2.5.0.
Everything works ok except sending any email to customer. 
 
Emails are sent only to shop owner but NOT SENT to customer.
** 
** 
*plugin.tt_products.email_notify_default = 1 *
and other settings
(plugin.tt_products.orderEmail_from,
plugin.tt_products.orderEmail_fromName
plugin.tt_products.orderEmail_subject)
are set correctly, I think.
 
Where could be the problem?
 
Dana Novotna