Block Calls

I contacted support to ask how to Block calls for our internal paging system for all external lines and only allow calls from internal extensions. Currently anyone can call that number send a page throughout the organization.

They told me to go to the extension and under the Block Option "All Calls" and put in our main number on the exception list. Well that Block All Calls with the exception does NOT work as intended. I am asking, to please fix things that should work. It is exactly the feature I need.