Background: Veribook is an online scheduling service used by medical clinics to enable their patients to schedule online. 

Problem: Sometimes we're advised by patients that the appointment confirmation that we send shows a time different from what was selected or booked.

Discussion: This issue usually happens if you are using Gmail, and your Google Calendar is incorrectly set to GMT instead of your local timezone. If this is the case, Gmail will display the confirmation time in GMT instead of your local timezone, and as a result, you might think the time is wrong.

For example, in the screenshot, you'll note that the first red arrow identifies a time that is in GMT, whereas the actual email sent indicates the time in local time (the second red arrow).

When this issue arises, there's not really a problem that requires fixing since it's the same time, regardless of the timezone (e.g. 9PM GMT is the same as 5PM EDT). You'll just have to pay attention to the timezone that Gmail presents to you.  

Here are instructions for how to adjust your Google Calendar so that this doesn't happen in the future.