It usually disappears when you change the visibility of the properties (or table columns). You can re-enable them by editing the file using an external editor.
For example, let’s say I have these tasks.
If I disable the type property from appearing in the table, then you can see in the back the clock-time
has disappeared now.
Now I can open this page in an external editor and fix it by adding clock-time
in query-properties
.