Your reZEN API Key can be found right within your account.
Step 1: Click the three dots on the bottom right of reZEN, next to your profile. Then click Security Settings.
Step 2: In the Recent API Key section, click + Generate Key.
Step 3: Name your key with whatever you want - this is a name you will use to remember it.
Step 4: Copy your key and paste into the application you want to connect to.