Why does the Postfixadmin error occur?

Question

bash

Good day!
I'm trying to install the Postfixadmin-CLI web interface on debian-9.0-x86_64-minimal using the following instructions:
https://linuxize.com/post/set-up-an-email-server-w...
, but how does it come to creating a user, the following error occurs:

Although the article describes that there should be a message:
Welcome to Postfixadmin-CLI v0.2
------------------------- --------------------------------------
The admin [email protected] has been added!
-------------------------------------------------- -------------
Does anyone know how to deal with this problem? Search engines do not give clear answers, although questions are asked on this topic.

Answer 1

Their wiki doesn't even have a command like "admin add". wiki
But they write there that the documentation is "outdated" and offer to run
postfixadmin-cli help , try it, maybe not really?
I'm editing the answer.
Found this discussion , with a very similar problem. There is a solution, though it will have to be corrected a little in the code