The ACS in question was NemID which had technical issues for a couple of hours. The issue is reported as resolved.
Monitoring · UTC
The issue has stopped and our partner reports the issue seems to have originated from a 3rd party access control server.
We will continue to closely monitor that everything is operating smoothly.
Update · UTC
We are continuing to work on a fix for this issue.
Identified · UTC
Our partner who handles the service which initializes 3DS requests confirms they are working on a solution on their end. We are awaiting further feedback from them and will provide an update accordingly as soon as possible.
Investigating · UTC
We are currently seeing a degraded performance in 3DS authentications. The issue is being investigated.