Right. Ssh is port 22 by default. Port 23 is telnet (deprecated) and it is possible that the remote client was trying telnet or was unable to manage the port correctly.
Your port forward is now working as expected. And, as promised by the contributors here.
Is there anything else that needs to be addressed?
If not,
If your problem is solved, please consider marking this topic as [Solved]. See How to mark a topic as [Solved] for a short how-to.
Thanks! 