If a Muslim eats pork by mistake is it a sin?Like if he ate a meal at a restaurant and was told it didn't contain pork when in fact it did?

If somebody accidentally eat it,then that's fine,say astaghfirullah and ask him for guidance and forgiveness. Quzibillahi Mina shytan Al Rajeem Bismillahi Al Rahman Al Raheem "He has only forbidden you carrion,blood and pork and what has been consecrated to other than Allah.But anyone who is forced to eat it -without desiring it or going to excess in it - commits no crime.Allah is Ever-Forgiving,Most Merciful"(Surah al-Baqarah:173)