I have manually changed a clock date range in a task's logbook using the shortcut =C-c .= (org-time-stamp). It modified the Org timestamp to the date I wanted, but changed the enclosing markup from [] to <>. I didn't pay much attention on it as C-c C-c (org-ctrl-c-ctrl-c) updated correctly the total time.
But it happens that the change from [] to <> markup is enough to let - clock table - org-agenda-columns' CLOCKSUM_T property completely ignore the clock entry I modified. I tested that after changing the enclosing markup from <> to [], everything works as expected. BTW, org-lint reports nothing on this. Below is a minimal not working example. 1. In ~/test.org, put the following content. * TODO Task SCHEDULED:<2021-03-13 sam. ++1d> :PROPERTIES: :Effort: 1:00 :LAST_REPEAT: [2021-03-12 ven. 12:39] :END: :LOGBOOK: - State "DONE" from "TODO" [2021-03-12 ven. 12:39] CLOCK: <2021-03-12 ven. 09:15>--<2021-03-12 ven. 12:15> => 3:00 :END: 2. Insert the dynamic clock table and press C-c C-c on it #+BEGIN: clocktable :scope ("~/test.org") :maxlevel 8 :block 2021-03-12 #+END: the task does not show up. 3. Put this file in your agenda files and set agenda columns (add-to-list org-agenda-files "~/test.org") (setq org-columns-default-format-for-agenda "%50ITEM(Task) %2PRIORITY %10Effort(Effort){:} %10CLOCKSUM_T") 4. Now open org agenda in "columns mode" (org-agenda-list) (org-agenda-columns) The task's CLOCKSUM_T field is empty. 5. Finally, replace the CLOCK property timestamp enclosing markup from <> to [] in test.org. Try again 2. and 4. Emacs : GNU Emacs 28.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo version 1.16.0) of 2021-01-20 Package: Org mode version 9.4.4 (9.4.4-27-gb712b9-elpaplus)