The former Manchester United junior was dropped after being late for two training sessions last week.
"I was wrong and I'm very sorry," he told Tuttosport. "And of course, I apologise because I know I have been disrespectful to boss Antonio Conte and my teammates.
"It was not my intention to do so and my delays are related to issues that are very trivial, but they are mistakes.
"I know that mistakes are also needed to mature and every experience is useful for the growth of each of us. I realised my mistake and I will do everything to make sure that it is not repeated in the future.
"I think the matter is now closed. And I have no intention of re-opening it by being late again!"