We are aware of an issue with some Apple email clients (from apple devices) having issues verifying our certificates on the mail platform. We are working on this and hope to have it resolved shortly.
You are welcome to raise a support ticket at the HelpDesk if you feel your issue is not related to this.
09:18 - Reported
10:30 - We have identified the cause of the issue which is an ongoing incident with our certificate provider.
11:30 - We've temporarily resolved the issue but are working to establish a proper resolution. There will be periods of instability during this time.
13:00 - Our certificate Authority has resolved the issue and our testing has confirmed this. We've switched back to the main certificate for our services.
We will continue to monitor the situation over the next few hours.
10:36 30/11/2019 - We are going to close this incident now since the issue has subsided and there are no new reports.