On 2025-02-02 08:38, Uwe Brauer via General discussions about Org-mode. 
wrote:
> Vale, entendido (supongo que eres español, porque usas la palabra movil,
> ¿correcto?)
Yes :D
   but let's keep the discussion in the mailinglist in English so other 
people can participate, or benefit from it
> Thanks, but I cannot find the function
>
> my/set-property-with-inactive-timestamp
>
> In your code,

In fact you don't need ~my/get-inactive-timestamp~ for your pursposes, 
try with this one:

#+begin_src emacs-lisp
(defun my/org-add-timestamp-on-heading ()
   (save-excursion
     (org-back-to-heading)
     (org-edit-headline (format-time-string "<%F>"))))

(add-hook 'org-insert-heading-hook 'my/org-add-timestamp-on-heading 'append)
;; to remove it
;; (remove-hook 'org-insert-heading-hook 'my/org-add-timestamp-on-heading)
#+end_src

but here you have for curiosity, there you can see compact strftime 
format to construct a inactive timestamp

[1]

#+begin_src emacs-lisp
(defun my/get-inactive-timestamp ()
   (format-time-string "[%F %a %R]"))

(defun my/set-property-with-inactive-timestamp (property)
   (interactive)
   (org-set-property property (my/get-inactive-timestamp)))
#+end_src