Hi,
In recent versions of HikaShop, there is a menu Customers>Emails history where you can check the emails sent by HikaShop. So you can easily see if the emails are being sent. With your version of HikaShop, this has to be done on the email server side, by looking at the logs of the email server. So you would have to contact your hosting provider...
I'm suspecting that the emails are actually being sent but they are rejected as spam or something like that.
I would recommend you to test to bid with several accounts using an email address from
www.mail-tester.com/
There, you can check if the emails are received and what kind of emails are received.