Problems with Rak3172 not sleeping

We have a module with RAK3172 and PIC on it. And our quest is, when we send the data, rak3172 and pic should sleep.
But our problem is when PIC goes to sleep, RAK3172 does not. RAK3172 tries to transmit data continually.
And also, we have the same problem with E78.

So i really wanted to ask you about it, what is the problem?