Mellow can only have one owner, but of course can be shared by multiple friends and family members.
If you received the error Unable to Connect, please contact the Owner of this Mellow, you can either have the owner remove this Mellow from their account (instructions below) or have the owner add you as a Family or Guest user.
To find out more information and setting up Family and Guest Sharing, please click here (link to HC article about Family and Guest).
How to stop being Mellow's owner
1. Tap on More icon (bottom right on main menu)
2. Tap on Settings
3. My Mellows
4. Select the Mellow you want to remove
5. Remove this Mellow and confirm