Why won't my wolves in minecraft stand up?

So I spawned few wolves in creative mode and then tamed them, so i played with them in survival mode too and they were great! They killed all the zombies and skeletons and spiders etc… But then when i quit the game ( i already saved and quit and in the menu i exited already ) and then few hours later i played again but all my dogs were SITTING! They woudnt stand up even if i hit them with something. Also my Minecraft is pirate does that affect anything? Please ANSWER As soon as possible