I have my renew page and my current (free) subscription is listed. I also have a premium subscription as part of my site. On the page the box to move to the next subscription which is the premium one is also there; however, the upgrade button is greyed out.
I viewed the source code and it appears the function display_upgrade_button() actually prints the button disabled. This is quite perplexing. Not only that, but the function takes 4 arguments but doesn't do anything with them.
How can I upgrade from one subscription to another? I have it set up in the admin back-end of WordPress already. Is this a bug?
Thanks in advance for any help.