Fireplace Guard Great Heist Help In Oblivain?

Great heist help in oblivain? - fireplace guard

I am on the arrow and killed the guards, but when he through the chimney and wokeup guard ran after me and when I to the monks, they also me while I was "captured and detained by a guard and then I ended up in prison , by Acting ANF again tried to open the door under the stage, and both were blocked Palace pickpocketing guards then tried the key, if anyone know what the hell I am the best way !!!!!!