Many actions for the same person at the same time

Hello,
I’m a new user of Dolibarr.
I’m interesting by the module ‹ Agenda › : It’s seems it’s possible to put two actions ‹ Rendez Vous › for the same person at the same time in two differents companies : does Dolibarr make some controls to avoid that ?
Is there a way to have some alarms for that or do i do something wrong ?
Thank you
Antoine.

There is no control for that.
Adding an alert should be a new interesting feature.

OK Thank you for your answer.