I have tried to add co-owner and it indicates pending, what needs to be done?

What was the result when you followed the guidance in the Related Article above your name on this page, that you were reading just before you posted here? If the Related Article doesn't answer your question please post back with more details about the issue and another user in this user-to-user forum will try to help.

Note that the co-owner must accept the invitation, and a credit check must be completed after they accept, as described in that article.