Android Q introduced a new security-focused feature called "Scoped Storage". This feature is introduced with Android Q and changes the way that app interact with the device's storage. Basically, with Scoped Storage, each app would have its own ‘sandbox' storage where it can run and store data. In turn, the apps would be limited to the sandbox and wouldn't have access to other parts of your storage. In its current state, Scoped Storage is causing issues with Android Q beta 2 users. Apps installed on the first beta worked just fine in the compatibility mode, which doesn't enforce the storage...
Source: https://www.gsmarena.com/android_qs_scoped_storage_requirement_for_apps_pushed_android_r_in_2020_-news-36787.php
