Why can't I escape from the seventh pass of Cao Cao Chuan?

This level is like this: Divide your fighting capacity into two waves, make the following Zhang Liao bet, and then return in the next round and beat back seven or eight steps. Another wave also hit the right side. Don't take a few steps quickly. The enemy will come to this level himself. This is not victory, but defense. After about eight rounds, someone will advise you to run away. You can leave Cao Cao where you came in, or you can just take a few more steps. Easy to escape.