Kill session not highlighted

When we were DBAs in an old environment, we had all abilities – of course.

Now that we are not, we are being given rights/roles as issues come up.

The latest is the inability to kill a session. While TOAD allows us to see the
sessions, the Kill Session is not available (un-highlighted).

Is this a function of TOAD, rights, roles or some combination?

What role/rights are required to have this ability?

It’s the ‘alter system’ privilege.