 Zheng then sought and received aid from Qibi Zhang (契苾璋) the military governor of Zhenwu, who launched Tuyuhun and Tujue soldiers to repel the Shatuo.Li Keyong was forced to withdraw north.He captured Xin (忻州, in modern Xinzhou) and Dai (present-day Daixian) Prefectures and made Dai his headquarters.