Sorry, post was in Xbox Forums.
This solution was posted in: http://answers.ea.com/t5/PvZ-Garden-Warfare-Playstation/Cannot-create-an-account-due-to-being-under-...
Problem: You have a kid whose PSN account is a subaccount of your PSN account. Your PSN account is tied to an Origin account, but your kid can't play at all when logged in as themself because they aren't tied to an Origin account, which is required to play *any* mode, seemingly.
Solution:
1) Download the Origin client for your PC or Mac. I didn't say this was going to be pretty :-) Log in as yourself, the adult.
2) Run the Origin client. Click on the button to see your Friends, then click on the button to "Add a Friend"
3) On the resulting screen, there are buttons to import Origin friends from various options, including PSN
4) Click on the button to import friends from PSN
5) Here is the important part. When you do this, it is going to ask you to log in to PSN so it can scan your friends and find friends that use Origin. The important part is: log in to the child's subaccount, not your adult account.
When you do this, it may or may not end up finding or adding any Origin friends, so if you actually care about that, be forewarned. But as a side effect, it ends up saying, "Huh. I guess that other (child subaccount) PSN account is also associated with this Origin account." So now your Origin account is tied to both the adult account and the child subaccount.
Once this is done, a really cool thing (in my opinion) happens. Not only does the child account work properly, allowing the kid to connect to Origin and play online, but it disables the in-game chat and messaging for the child account. For my purposes, this is actually really appropriate and smart. I think it is a shame that the integration is so nice, but impossible to find.
