when we refold just 1 drop-down list,

Which drop down list ?
Do you mean projet level ?

Yes at project level

Can you check and report WBS of each project.

Also try and move one of the project, they try again...

As you can see on attached files, it is an issue at "real work allocation " sreen...

There is only tasks where resource is assigned in this view and not all the wbs of the project.

This issue appears when you want to refold just one drop down list==>2 drop down list are embedded rather than one.....

There is only tasks where resource is assigned in this view and not all the wbs of the project.

This is normal, exactly what is designed.

This issue appears when you want to refold just one drop down list==>2 drop down list are embedded rather than one.....

I understand that the issue appears on Real Work Allocation.
Source of issue may be incorrect WBS. So to try and fix my proposale is to go to planning view. and move the projects : for instance set them as sub-project of another project, then back to their correct place. This will force re-calculate of WBS and may fix the issue.

Ok issue fixed moving project wbs....