The Brazil forward openly discussed the fact he wanted to leave the Parc des Princes after two years with the French champions but says he is no longer at odds with the club.
PSG fans booed Neymar when he made his return to action this season, yet he has responded by scoring four goals in five Ligue 1 appearances.
At a news conference on the eve of Brazil's clash with Senegal, in which he is set to win his 100th international cap, Neymar said: "Everyone knows what happened in the summer market and the desire I had to leave.
"Today, I feel happy and comfortable with the club, too. It's not just with the national team that I'm happy. The season started out very well for me.
"I will defend my club tooth and nail. I will give 100 per cent for us to achieve great things.
"It was a long summer for me. I knew that I had to prepare, in all circumstances, for a good season. Thank God, it has started well and I hope it stays that way."
The 27-year-old forward missed three months of the 2018-19 season with a foot injury, similar to an issue he suffered in the previous campaign.
The problems restricted Neymar to 20 Ligue 1 appearances in his first season in France and just 17 in his second, and he has targeted a healthier, more fruitful year for Thomas Tuchel's men in 2019-20.
"There have been more than three months of injury treatment in the last two years," he said. "This gets in the way of any athlete.
"But if you look at all the games and numbers you will see that I never stopped playing football. Unfortunately in an athlete's life, this can occur. You have to have a good head and be prepared to go through it.
"My hope for this season is to stay fit, to hope that nothing bad happens."