I have changed my default portal to "Understanding Decisioning" Portal . Now I am not able to revert back to my Admin portal. Could anyone help me on that. There is live UI option present in this portal.
Did you try logging in with firstname.lastname@example.org Operator ID and are there no Operator ID's present which is pointed to Dev Studio.
If the above is not working, from live UI is it possible to open any activity rule, or from tracer steps open any activity rule and from there we can Obj-Open-By-Handle the access group and change the Default portal and commit the changes.