Crawley Town lodged an appeal with the FA following an incident during Saturday’s 4-1 defeat at Accrington Stanley.
Midway through the second half Walton was shown a red card along with two Accrington players, Shay McCartan and substitute keeper Jason Mooney.
McCartan received his card for his challenge on Crawley defender Jon Ashton, causing him to leave the field.
Huge 6ft 8.5 ins tall ‘keeper Mooney was sent-off for going on to the pitch and joining the fracas from the subs’ bench.
Accrington have also appealed against his red card.
Reds officials thought it was a case of mistaken identity.
Chief executive Michael Dunford said: “We have reviewed the video and we can’t see any evidence of anything which warranted a three-game suspension.
“The player categorically refutes that he has thrown a punch.
A Reds statement said yesterday (Tuesday): “The Football Association said there was insufficient evidence to rescind the red card punishment at a hearing today.
“Simon will now be banned for three matches against Plymouth Argyle, Leyton Orient and Newport County.”
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