How to restrict access

We have defined two Category set.

1. FTSL IGC Accounting , Flex Structure : Accounting Category

                                          Controlled at : Master Level.

2. FTAI IGC Accounting , Flex Structure : Accounting Category

                                         Controlled at : Master Level

where we have assigned the same category is also assigned these two Category Sets.

Now we need to restrict User accessing different entity setup.

How can this be achieved.

Thanks

Vinutha.