Thank you for your feedback.
To change the sending name in Yahoo Mail, please follow these instructions:
Please note: Some third-party apps have their own sending name setting, which bypasses the Yahoo Mail setting. If the app you're using attaches a different name than the one saved in your Yahoo Mail settings, contact the manufacturer of the app for assistance.
Yahoo Support Team
An error occurred while saving the commentFloyd A McCauley commented
how long after i change it and save it does it take to really go into effect.. right away or a day or 2.. after I changed it under the account tab this time and the personal info, I sent a test from yahoo mail to my daughter account and still says Dad name..