Our sincerest apologies for the inconvenience.
The outage was caused by a failure affecting the storage system, through which the email systems operate. The failure has meant that customers have had difficulties using the email systems during the period of outage. Our network Engineers are actively working to resolve the issue at the earliest.
We've posted an update here in the community. You may refer to [Update] TPG Email Outage.
Further updates will be posted on our service status page and here in the community.
Thank you for your patience.