You can't take the bolt out of a Mauser if it is not cocked, so somehow the bolt became uncocked. Place the front edge of the cocking piece on a sharp edge, like a board or the edge of a bench and push down on the bolt, forcing the cocking piece back. When it clears the safety, turn the safety to the middle position. You can then unscrew the bolt sleeve and disassemble the bolt or turn the bolt sleeve clockwise (as viewed from the back) until it stops; then you put the bolt back in the rifle.
Jim