Failed to use a tutorial: cannot resolve symbol

Hi everyone,
I am new to ScalaPB and started by using the tutorial by downloading the project from github:
https://scalapb.github.io/docs/getting-started

I managed to generate the codes after sbt compile in (as explained in the tutorial):
target/scala-2.13/src_managed/main/scalapb/com/example/tutorial/addressbook

but I got errors with the main code as on the figure:

My main question is how to use the generated codes (case classes for each message) obtained after compiling since they are in …\target\scala-2.13\src_managed\main\scalapb\tutorial\addressbook\

Also, in the codes from github, there is no tutorial package in /scr/main/scala/: I tried to refactor and create a tutorial package as
\basic\src\main\scala\tutorial\AddressBookMain.scala but I got the same errors: Person and AddressBook are not found.

Coud someone help me with those please, I am really stuck with this (I use IntelliJ IDEA)
Thank you very much,
Best regards.
Maia

Seems like an issue with the repository you cloned, maybe open an issue with the devs on Github? Link