Referee Keith Stroud has apologised for his blunder at St James's Park.
Ritchie scored Newcastle United's winner in tonight's 1-0 win over Burton Albion at St James's Park.
But the winger also had a first-half penalty, awarded for a foul on Dwight Gayle, ruled out because of encroachment.
Stroud, wrongly, awarded a free-kick to Burton.
The decision sparked protests from Rafa Benitez and his coaching staff as well as the players.
And Professional Game Match Officials Limited have admitted the kick should have been retaken.
A statement read: "In this evening’s EFL Championship game between Newcastle United and Burton Albion, referee Keith Stroud awarded Newcastle a penalty in the 29th minute.
"As Matt Ritchie took the kick, Dwight Gayle encroached in the penalty area. An indirect free kick was awarded to Burton, but the Laws of the Game state that that the penalty kick should have been retaken.
"Unfortunately the referee has misapplied the Law. Keith and his team are understandably upset at the lapse in concentration and apologise for the mistake."