Block messages between users in CUCM

[Firework]

Hello everyone.
I have UCM (latest version) + Expressway 14.2.7, MRA mode enabled

My question - is it possible to block correspondence between some users?

For example i have 10 users and i need to block any contact between user5 and user7 ( calls and messages ).
I found info how to block calls between them but i can't find info how to block messages. Is it possible?

I really appreciate any advice.

[Jaime Valencia]

Assuming you mean admin configured, not out of the box, you would need a 3rd party product that incorporates ethical wall.