Cowork Not Delivered Message

Yes happening for us as well across all enabled Anthropic/Frontier users and very frustrating. When opening the agent, the recent tasks section just has the purple animation, but never loads. Interestingly, when I ask Cowork to draft an email, it goes away and thinks for a while before coming back with the "Not delivered, retry?" message, but I do get the email created in my Drafts folder in Outlook. It seems to me like the Agent can't connect to the backend processing to get messages, results etc. I've asked our security team to check if there are URLs getting blocked or something.