"Mr. Miodrag Radulovic is informed that a repeat violation of this provision may be met with more severe punishment," the AFC said.
Lebanon's opening goal in the first half of their defeat by Qatar was disallowed before their opponents scored twice after the break to seal the win, leading the Montenegrin manager to question the match officials.
Media reports had quoted Radulovic as saying his team played "against 12 or 13" and accusing the officials of denying Lebanon a legitimate goal.
Lebanon lost to Qatar and Saudi Arabia in Group E but have a slim chance of qualifying for the knockout stage as one of four best third-placed teams if they win their final group game against North Korea on Thursday.
(Reporting by Rohith Nair in Bengaluru; Editing by Amlan Chakraborty)
