Responsibility access with a Role

We have a responsibility where the majority of the functions are read only. The SIT function is not, but 1 SIT is not marked as updatable or Insertable within the segment structure. We created a role that allows certain responsibilities the access to update and insert. All responsibilities but one are able to update/insert to this SIT once the role is assigned. Any pointers or help is appreciated. We are on Oracle EBS 12.2