Verification code problem!

In the Events Booking on my website - When I try to register for an event and fill in the verification code, it says that it's wrong. But I've done thi more than 5 times in a row and I'm 100% sure that the code I type in matches the verification code but I still get the error message. Why is this?

Hi

That's strange. What version of the extension you are using ? Could you please send me the link to your so that I can have a look at it ?

Tuan

I'm using Event Booking version 1.4.5,. Strange - now it appears that sometimes it works and sometimes it doens't. Now I'm having a problem with the mailfunction. After I test to register for an event it simply says "Kunde inte initiera mailfunktionen" (in Swedish) It mean: Could not initiate the mailfunction. In other words - no notification e-mail is sent to me, the admin, and no e-mail is sent to the user who registred to the event either. Strange, because this has been working fine all week. What could be the problem here. I have not changed anything in the settings.
The link to register for events is: www.webbplats.personaliaab.se/index.php/anmalan-till-kurser