Because the game is still in progress and there is card fog, it’s impossible to tell at this point.
Full game link is http://warzone.com/multiplayer?GameID=18284640
In the settings, diplomacy card should last for 2 turns.
I assume by “move” you mean “turn”.
Which turn did you play the card on in your example?
Edited 8/25/2019 18:41:00