"Session expired or cookies are not enabled in your browser"

CBSubs Tax is installed and published.

System - Community Builder plugin is first and enabled.

Problem persist. Any other suggestions please?

Is the spoof checking within CB > Configuration > Integrations important? I have recaptcha on the registration page.

I found out where the problem comes from. It something to do with the "Invoicing address handling at payment time", it was Mandatory until now, I made to "No invoicing address shown" and the registration completes good now and session problem is gone.

?

Why in the "CB fields for first invoicing address of customer" there is only one Name field? I think the problem comes from there. I'd like to be able to select a First name and Last name fields so they can be pre-populated automatically from the the registration fields. Currently the name is missing in the invoices!

I found out where the problem comes from. It something to do with the "Invoicing address handling at payment time", it was Mandatory until now, I made to "No invoicing address shown" and the registration completes good now and session problem is gone.

I don't see how that could cause your issue. I've tested here and couldn't confirm. My guess is you've a caching problem. At any rate spoof checking can be left disabled if needed.

Why in the "CB fields for first invoicing address of customer" there is only one Name field? I think the problem comes from there. I'd like to be able to select a First name and Last name fields so they can be pre-populated automatically from the the registration fields. Currently the name is missing in the invoices!

Right now you can't. We've already a pending ticket to fix the Name field mapping as it's currently just 1 field instead of conditioning to the configuration format.

I'm not using caching at all.

You have implemented the fields here on joomlapolis.

Anyway,
Thank you

I'm not using caching at all.

That's the only reason for the session expired error. I have yet to find any other causes. I don't know what more to advise other than leave spoof checking off. It could be a conflict from a 3rd party extension maybe altering the post data or session data perhaps.

You have implemented the fields here on joomlapolis.

We're on older releases until we've migrated to our new redesigned Joomlapolis. Your issue is a new bug due to XML usage changes; specifically the input isn't letting you select the Name field.