My cookies cannot be deleted in Safari 12.0.2

I am running Safari 12.0.2 in conjunction with Mojave 10.14.2. In the past, while running Safari I could go to Safari--->Preferences...--->Privacy and then click on Manage Web Site Data... to see all of my cookies and delete the ones I want to, like this:

However, in the last week or so this no longer works. Instead, the next page pops up, but there are no cookies displayed, and even searching for a specific cookie yields no results, like this:

Any idea what is going on here?? Thanks!