I just finished the free trial edition of Zoho Creator. My account automatically switched to the Free version. Since I can't use subforms with free edition, I would like to use the Developer edition. I'm in the developing phase of my project and I don't want to spend money until the app is ready to use.

I can't figure how to convert an existing free edition account to a developer edition. The following link allow new user to signup to developper edition :

https://www.zoho.com/creator/developers/signup.html

But when I enter my email, it says "An account already exists for this email". When I go through the "Upgrade account" process, it only allow to upgrade to a paid version.

So, how can I convert my existing account subscription to the Developer edition ?

Thank you !