Records can be deleted only by their owner. Here are links to our official documentation where you can find more information how to delete records using QuickBlox SDKs or Server API:
Server API - Custom Objects | QuickBlox Server API
Android - Custom Objects | Android SDK | QuickBlox
React Native - Custom Objects | React Native SDK | QuickBlox
Flutter - Custom Objects | Flutter SDK | QuickBlox
Feel free to check our official documentation for more information that will help you to integrate QuickBlox services into your applications / projects or contact our Support team by submitting a ticket if you have any other questions.