At this time we have identified an issue with accessing our Duo Administration site and there may be delays or timeouts with other Duo authentications, such as push notifications and SMS authentications.
Please see the status provided by Duo:
We are currently investigating an issue with authentication delays, timeouts, and issues loading the Duo Authentication Prompt iframe on multiple deployments. We are working to correct the issue as soon as possible.
We will update this status once more information is available.