Most likely the problem is that you are using Safari in Private Browsing mode. Fortunately, the fix is simple: turn off Private Browsing. Here are instructions on Apple’s website:
https://support.apple.com/en-us/HT203036
Many people are not even aware that they are in Private Browsing mode. But some users are under the impression that Private Browsing offers more security than normal browsing. This is not really the case. Private Browsing disables a bunch of browser features to prevent Safari from remembering whatever websites you happen to be visiting. This can certainly be useful on occasion. But it also degrades your experience on many websites (such as Tikkit) that rely on these browser features.
Except for times when you specifically want to block Safari from keeping a record of your web history, we recommend using Safari in normal mode.