Firebase Shows Wrong Data On iOS

[tal412]

I use some of the Flutter-Fire plugins in my app (I don't use the Firebase Analytics plugin).
I initialize Firebase normally in the main() method like this:

await Firebase.initializeApp();

My problem is that only the Android app is being tracked by Firebase.
The iOS app seems to prevent Firebase from tracking user's data or something...

For example, the Firebase dashboard indicates that the "Daily active users" is about 195 on Android, but 1 or 2 on iOS:

This data can't be true according to the Apple Connect stats and AdMob stats, which shows about 100 active users per day.

Another example is the latest release, which shows me that the latest release for iOS was a few months ago (and again, this is not true - Android and iOS have the same version - 1.3.3):

What could be the problem?
The data was accurate also in iOS a few versions ago, but something has changed...