Use APKPure App
Get LigarCobranca - Robô Telefonis old version APK for Android
Enter the battle and automatically call (repeatedly) for collection companies.
Based on the call-to-charge package, this application will do all the work for you to simulate the same as billing and telemarketing companies do:
Switch on automatically and repeatedly.
Using a VoIP API, with only 3 fields and no need to register in the application, you can orchestrate your revenge.