Keep having to change twc.com email password

Have a family member who has a twc.com email address as his main email. He does have spectrum internet service. This is probably something that would need to contact spectrum about eventually.

For whatever reason, every so often, he keeps having to change his email password. Will be working fine one day, next day it will not recognize his password. I change it and it will work for a while. Going to try and keep track of how often this is happening. Trying to figure out if this is something he or someone else is doing or if this is on spectrum's end. Has anyone else had this issue before and what was done to stop it?