I had a similar problem with the Fongo (free voip number) app. My account was suspended because I was using an unauthorized app store, in this case Aurora Store, to install it. I confirmed that with the app developer and found out that they only will allow installed from supported app stores (e.g. Google Play, Apple, Amazon)
I didn't realize that there are identifiers in the OS that show where the app is installed. Settings > Apps > select your app > and page down to the bottom where the Store / App Details is shown. If it's not the Google Play Store, it will state Aurora Store, F-Droid etc.