Zombie Pigman got angry.

I use a 64bit system and the last version of java. I have a big problem with pigman zombies. After accidentally hitting a ZP a few days ago he obviously got angry. I thought that after waiting a few minutes they would calm down,but they killed me. After that i waited for AFK two hours in the nether the pigman were still angry. I didn't know how to solve and i tried to kill them all in creative but respawn a pigman that reloaded the others. I tried to go peaceful and then put the hard mode back on. I tried to leave chunk to reset it going far but also returning to the starting chunk pigman are angry with me for no reason. I really tried everything that is in the minecraft rules and it doesnn't work. I can't go in then nether. I'm on 1.14.2. Sorry but i'm italian and I don't speak english very well.