I deal with this all the time. Customer switches ISP and forgets that they also provided email account. A year later, without notification, the ISP purges email account. Get her to switch to Gmail or some other email provider that is not affiliated with an ISP now, while it can be done gracefully and on your terms.
Frontier has also "capped" service to numerous neighborhoods in my area. They over-sold the service, selling more than they could provide. Now there is no new service available, even if someone has cancelled. For some reason the speed still doesn't improve.