The text and recordings you upload, and the audio you generate, remain yours. You give us a non-exclusive, royalty-free licence to store, process and copy them to run the service and to train and improve our models. Delete the content or your account and it's left out of future training; models already trained keep what they learned.
Only upload content you have the right to share this way, including recordings of other people, and use it lawfully and without infringing anyone's rights.