[SOLVED] strange behavior using planned date for project (bug ?)

Hello,
We are currently using v9.2.4.
Using project and planned date, I come accross a strange behavior (maybe a bug ?) on all of our project.
I have a created a very simple project for the purpose of the explanation (see screenshots : project 75, activity 319 and activity 320):
- The project 75 has 2 activities, linked with a dependancy (319 « lancement » is predecessor of 320 « réalisation »)
- The project starts the 04/10/2021      
- The two activities has an assignement (resource Test chef de projet), for 5 days each
                o   The resource is not staffed on any other project on october     
-  Activities are on « as soon as possible » planning mode 

My understanding, after reading the user manual, is that planned date are calculated using the assignement, dependencies and planning mode. In my case, I am expecting an activity 319 ending on 08/10 and the activity 320 to start on 11/10 and finish on 15/10.
After clicking on the calculate capacity planning button (the calculator) using the date of 04/10, I have the following (see screenshot planning gantt) :
 -  Activity 319 starts on 04/10 but has one day of duration
- Activity 320 starts on 30/09/2021

Am I missing something regarding planned date ? Is it a bug ? I can provide more information and screenshots if needed.
Thanks for your help ! 
Best regards

Hi,
you are right ! Capacity was 0 for this resource.

I'm a bit confused because these resources were created from an import and I was assuming that everything was right... I will check it for every resource now.

It could be a great improvement to make the field mandatory in a future version, in order to make users look at this field.

Everything works fine now. Thank you for your help