I've asked that full access is restored for the mailbox email address in your Community profile, Personal information, Private notes. (Do check it's there - master mailbox address if using an alias address)
TalkTalk Support will respond here and then restore MAP4 / POP3 access as soon as reasonably possible. Until full access is switched back on, ask the user to use TalkTalk Mail webmail via an up to date Internet browser to keep in touch with email contacts.
Are you confident that no help is necessary checking the services / devices / email software for compatibility with TLS 1.2 encryption and the incoming and outgoing server settings in use? Did you identify the insecure settings, for example? The culprit device or software that got a stop on sending or mailbox access switched off because ports 25 (SMTP) or 110 (POP) or 143 (IMAP) were used?
