A useful prompt can still be a private one.
People, email addresses, phone numbers, and account references are exactly the details a model does not need in order to help with the writing.
Draft a follow-up to Amelia Rossi at amelia.rossi@northwind.example about account 4412-8831.
Draft a follow-up to [PERSON_1] at [EMAIL_1] about account [ACCOUNT_1].