I have been using actionable message in my email for a year. However, I suddenly keep getting "An error occurred. Please try again later." whenever I trigger Action.Http now. This happens to both new and older actionable message and with both outlook desktop client and outlook webmail. Upon inspection, I noticed there is an (500) Internal Server Error thrown by https://outlook.office365.com/actions/userid/messages/{key}/adaptiveCard/executeAction?culture=en-US.
What might be causing this and how to resolve this issue? This issue also happened to several other users in my company previously.