Question: By Section do you mean "Related Information Section" or a Section on the Parent Object link (Contact Information, Address Information etc...)
If it's Related Information Section then then you could look at the below points
The reason this could happen is that someone may have logged in with that user id and personalized it, by going to "Edit Layout" on that Object's Detail Page. There will be 3 links below the Web Tabs. Click the "Edit Layout".
By section I mean Related information layout.Actually I need a add a section Exclusion in Appeal Objects.At related information layout at page layout of Appeal level,I am able to add but at My setup of appeal layout ,I am not able to see that related information layout.I have tried at production level and I am able to add that section but in staging I am not.