play protect does not recognize this app's developer
Solution 1:
The Google app bundle format uses your certificate from the app as an upload certificate. Google generates a new certificate after upload that is used for app signing. So since your app is not uploaded and published, there is no signing key, and app is blocked by play protect when you try to install it locally.
Solution 2:
I released 1.0 version earlier. Now released 1.1 version.
1.0 before uploading on to Play console, I was able to install signed release apk, no issues.
1.1 before uploading on to Play console, I was - not - able to install signed release apk, and failed.
Looks like, play protect gives this error for an already released version on play store, if so, so this message should be seen as normal.
Once the 1.1 is pushed to play store, I saw no issues, so this error was just a false negative and can be ignored if you are updating the app.
Solution 3:
Yes!
Because you are not publish through Google Play Store and Google Play Protect uses the list of registered developers to identify the app installed. Since you have not publish through play store before, you will always get that message.
Hope it helps!
Solution 4:
You will indeed have to upload your app to the google play store in order to eradicate this problem! Google has a list of verified developers who have already published their app to google play and thus they don't face any issues. Since you have not uploaded your app to google play, you will face the issue. What is happening is that google play protect is not able to recognize you as a developer as you have not uploaded your app to the google play store. Uploading your application to the google play store will help you get rid of this unrecognized message by google play protect. Edit: Please Contact Google if you have any errors.