Ionic is not syncing data to Cast S41

[Yfaineiv]

Just got the ionic and it tracks me all day but I'm having alot of issues. Like it not tracking my sleep and it not saving data from past days. I updated the app and nothing has changed it will track all day but when I wake up the next day all my data is gone please help. I am using a cat s41 phone could this have anything to do with it?

Moderator edit: updated subject for clarity

[MarreFitbit]

It's nice to have a new member around, welcome @Yfaineiv! Note that the devices on this list have been confirmed as fully compatible with all features of Fitbit devices and the Fitbit app. While a phone or tablet may not be verified as fully compatible, the Fitbit app may still work with your device. 

Our team routinely test new devices to ensure full compatibility with Fitbit devices and the Fitbit app, and are constantly working to confirm compatibility with new phone models. Be sure to verify that your phone meets the minimum operating system requirements. Note that the majority of Android phones running version 4.4 or higher will work with our products. 

If your phone supports Bluetooth 4.0, I'd recommend giving the setup flow a try to see if you can successfully connect your tracker. On the other hand, if your tracker is already paired to your phone, but it keeps failing to sync to it, see: Why won't my Fitbit device sync?

Please keep in mind that when a device is not supported we cannot guarantee its functionality with the Fitbit app. It might work at a certain time and then it can stop working out of nowhere after an update. This is because the app is not optimized to that device and any change could impact the performance.