Build Android app

Why isn’t building the Android app? A couple of weeks ago, everything worked, but after a week it stopped and no one from the support responds to letters about this problem. Is the support live?
In the menu item Download, press the Build Android App button, the build process is initiated, the indicator spins for a while and there is no result! Where to get .apk and .aab files???
I paid for the service for a month for testing, but now I understand that I just threw away the money.