I upgrade the EXM to version 3.1 Update 1 (3.1.1). Now when I go to create an One time message I don't see my email templates. I have add the email templates using the Insert options as bellow.
But still I don't see my email templates when try to create an One time message.
I have similar problem. But I've carefully read PDF file instruction for upgrade (Sitecore EXM 3.1) and found solution:
For each EXM manager root, change the item name of the following items:
EXM looks in the Message Type folders, in this case "One Time Message", and finds the first item with the right template, in this case "OneTime". Try moving your "Default" node to the top of the "One Time Message" folder.