Syncing an Ace

[cinnnql]

I bought my son an Ace and set it up on his iPad a year ago. It was syncing fine for a while, but he stopped using it for several months. When I tried to sync it again, I had to install the app and set up the Ace again. Now his app shows stats from my Alta HR instead of the Ace, and my app on my Android phone shows that it synced both the Alta HR and the Ace. How do I get the apps to sync up only with each respective device? Has this happened to anyone else? Any advice would be greatly appreciated. Thank you.

Moderator edit: subject for clarity

[LiliyaFitbit]

Welcome to the Fitbit Community, @cinnnql. I am sorry for the delayed response.

I appreciate your participation in the Forums and sharing the details of the difficulty you're experiencing with your Alta HR and your son's Ace. It seems there is some kind of confusion and I recommend confirming which trackers are paired to your Fitbit account and, if necessary, to remove the device from your account by following the steps from this help article: How do I remove a Fitbit device from my account? 

After that you can confirm the steps to set up the Ace tracker here. Since your son has his own iPad, you can follow the steps to set up the Ace from his device. If the tracker is paired to your son’s device, it syncs every time your son opens the Fitbit app.

Let me know how it goes, I'll be around!