Had a similar situation with my mother's iPad and Yahoo. YahooMail wouldn't allow a password change because my mother, having suffered an injury, moved and gave

Had a similar situation with my mother's iPad and Yahoo. YahooMail wouldn't allow a password change because my mother, having suffered an injury, moved and gave up her landline phone number, and had no alternative verification mechanisms set up. The native iPad mail app still connected via a cached credential, but those credentials can't be backed up. The iPad power failed sporadically, so she lost contact with people, with no way to transfer credentials to her new device (on the rare instance the iPad would briefly start), and no way to reset the YahooMail password. The only solution I heard that might work is to buy a paid yahoomail account on her behalf (assuming there's some way to verify her identity) and see if someone in support can get her back on the right track so that she can keep getting her spam and point anyone contacting her to her new address. I hope this stuff gets easier before I get to my 90s.