Project Scheduling issue in the project planning board

Dear PS experts,

     I have an issue while making project scheduling i have a project as below:

WBS 1 ---------------
Act 1    -------
            ACT 2--------

                       WBS2-----------------
                        ACT 3--------
                                   ACT4 --------

all the activities is FS relationship

when i trying to change the relationship between act 2 and act 3 to be SS
scheduling conflict happened as the dates of ACt 3 , 4 and WBS 2 doesn't changed .
my scheduling method : WBS determine dates so the dates of the WBS should be cleared manually and after that making scheduling

I have attach a file of my scheduling configuration.

and i am asking if anyone have automatic solution for this issue ???