Unfortunately there is no way to convert a full featured version of ECIQ to Connect, you'd need to register for a new account and build from scratch. I've sent you a temporary key to get you back in to the trial ECIQ instance so you can remove your devices from the old inventory. Once you've done that you can add them to your new Connect inventory.
This guide reviews how to register for a Connect account: https://thehivecommunity.aerohive.com/s/article/Registering-for-HiveManager-Connect
