Commerce Error - "Address requires the commerceguys/addressing library"

Hello, I would like to enable the Commerce and Opigno Commerce modules. When I go to /admin/modules and select "Commerce", and click save, I get the following error message: "Address requires the commerceguys/addressing library." Notes: - Opigno was installed via composer. - I have read through the Commerce documenation and understand that it also needs to be intalled via composer. But, it seems to have already come with the Opigno distribution so I did not do anything special for Commerce. - In my /vendor/commerceguys folder I see the following 2 directories: 1) addressing 2) intl So, it seems like the addressing library files are there but something is missing for the system to know where to find them. Any help you could provide is greatly appreciated! Julie