Sending remote break on ConnectPort LTS 32 serial connection

I am tying to send a remote break to a serial connection in order to activate kdb debugger.
I am connected to the Digi via ssh/telnet (tried both).

AFAIK, the break sequence should be CTRL-]
This is also well documented in kdb docs - https://www.kernel.org/doc/html/v4.16/dev-tools/kgdb.html:
When you have telneted to a terminal server that supports sending a remote break
Press: CTRL-]
Type in: send break
Press: Enter g

Unfortunately, this does not work…
I’ve also tried using a Putty telnet client and send Break using the special command menu, but this also failed.

I appreciate your help…