Why did Zheng Chenggong lose Taiwan Province Province after recovering Taiwan Province Province? Write down the reason and the result.

After Zheng Chenggong recovered Taiwan Province Province, he carried out a large number of immigrants, which promoted the economic development of Taiwan Province Province. Later, Zheng Keshuang, the grandson of Zheng Chenggong, defected to the motherland, and Shi Lang, then the prefect of Fujian Water Army, recovered Taiwan Province Province.

Later, because Shi Lang also defected, Taiwan Province Province was lost.