Notification of Returned Communication within a Case

We've been live on Creatio for about 4 months now and one struggle our team is having, is keeping up with returned communication within cases. 

For example: 

Consultant emails Customer from Case, and changes Case stage to waiting on customer. 

Customer responds to email and case is updated. But here is where we are lacking a notification to the consultant so they know the information they need and were waiting on has been returned. 

I"m sure there is some feature or workflow that's being missed. Can anyone advise and type of workflow or setting that can turn on email or message notification when the communication is returned from our customers?