Originally Posted by
davisew
You can't change into an EC seat on the app. You can change from one EC seat to another EC seat, but the app doesn't have the capability to process the transaction needed to get you into an EC seat (whether or not you have to pay for it).
I have found more than once where TAs, res agents, and Sky Club agents see all EC seats as occupied even when there are seats open that will show on the app and dl.com and you can get them yourself on the web.
+1 on both accounts
If you can see the EC seat on the app, that is likely correct and not the agent. As previously noted, you cannot move from a non-EC seat to an EC seat using the app, but @DeltaAssist can put you in the EC seat if it is free, though not if you have to pay anything (since they apparently can't do revenue transactions).