I′ve got a problem regarding the companions quest line! Aela have sent me on a animal extermination misson to Followstone Cave to kill some bears. But when I arrive to the cave it′s empty because I′ve been there and cleared it out in a preavious mission(Ogre mission)!
I′ve tried to reaload and go in and out but nothing happens, I′ve searched in different forums but no one seams to have this problem!? Can anyone help me solve this!?

No one??

Load a save before you got the mission?
Wait until the cave respawns? (30 in-game days, IIRC).
Use setstage CR02 20?