In your phrase you mix update reference for "Activities" and "change reference on type or project change : No" that don't has same effect.

Can you explain your use case ?

Hello,

Sorry for the time of response.

On the menu "Parameters > Global Parameters > Miscellaneous", in the section "Format for reference numbering" I have configured the parameters like that :
prefix format for reference : {PROJ}-{TYPE}-
number of digits for reference number : 5
change reference on type or project change : No

On the menu "Administration > Maintenance of data", I have selected for the parameter "update reference for : " the value "Activity", and I have clicked on "Update".

So I expected to have this type of numbering :
PRJ01-PHA-00001
PRJ01-TSK-00002
PRJ02-TSK-00003
PRJ03-PHA-00004

But when I do the update, I got that :
PRJ01-PHA-00001
PRJ01-TSK-00001
PRJ02-TSK-00001
PRJ03-PHA-00001

Thanks
Florent

Thank for the explanation. It's clear.

In facg, reference numbering works as expected.
Just a short explanation.
In peojeqtor, each item has an id, which is shared amonst all items of same class, for all projects.
This means that if you create a first ticket for project 1, it gets id 1.
Then if you create a ticket for project 2, it gets id 2.
And if you create another ticket on project 1, it gets id 3. So tickets on project 1 are 1 and 3 : there is a hole in the numbering.
Idea of reference is to provide a number that will be unique for a given project and/or type.

You defined a prifi {PROJ}-{TYPE}-
So numbering will be unique for Project code and Code of type.
If you want unique sequence for all items of same project, you need to define reference as {PROJ}- only, or define same code for all types of activities.