Alli threw himself to the ground after 73 minutes of Tottenham's 1-0 win at Selhurst Park in an attempt to convince Kevin Friend that he had been fouled by goalkeeper Wayne Hennessey.
The Spurs midfielder had already been booked twice for diving this season — against Huddersfield and Liverpool — and, although Friend did not caution him on this occasion, television replays showed clearly that he was guilty again.
As Tottenham were not awarded a spot-kick, Alli will escape retrospective action from the Football Association.