Bind parameter from a field not working

Hello,

I have a a field binded to a parameter :

This field would allow me to specify the SQL environment to be used in the query : 

But when i change the selection of this field in this slicer, the value is not updated in the parameter : 

the part when i change manually to other environment makes the change in the query. So my problem is really the binding.

Any clue how to fix this?
thanks in advance!