This issue can apply to people attempting to register for your events using the Register Page. Firstly make sure they are using the correct link and have actually arrived at your Register Page. If that is the case, here are usually only two possible reasons for subsequent problems:
Problem #1 - Internet Connection: they’re actually not connected properly to the internet. This sounds unlikely, but it can happen. A recipient's internet connection could have been interrupted while attempting to register.
Fix: check with them to make sure they have an internet connection. Ask them to load your company website for example, or download their latest emails.
Problem #2 - Internet Explorer users: some people / companies still use a deprecated version of Internet Explorer. This affects about 2% of Internet users in the US. Unfortunately Seatrobot (and Microsoft!) no longer support these old browsers, which present severe security issues and cannot handle the latest web technologies. It could be that the browser managed to load the registration page, but after they filled in their info, the browser cannot connect correctly to Seatrobot to send us their information.
Fix: Ask them to go back to the link, right-click and copy it and paste it into the address bar of ANY other browser - e.g. Google Chrome, Safari, Firefox, Microsoft Edge etc.