Manasseh humbled himself and God was moved by his entreaty

2 Chronicles 33:14-20
Manasseh, he got rid of the foreign gods and removed the image from the temple of the Lord, as well as all the altars he had built on the temple hill and in Jerusalem; and he threw them out of the city. Then he restored the altar of the Lord and sacrificed fellowship offerings and thank offerings on it, and told Judah to serve the Lord, the God of Israel. The people, however, continued to sacrifice at the high places, but only to the Lord their God.
His prayer and how God was moved by his entreaty(懇求), as well as all his sins and unfaithfulness, and the sites where he built high places and set up Asherah poles and idols before he humbled himself—all these are written in the records of the seers.
Why?
Manasseh regrets what he had done, he realized that God is the Lord. So he got rid of the foreign gods and removed the image from the temple of the Lord. He restores the altar of the Lord and sacrificed fellowship offering and thanks offering on it.
Anyone who was evil and turns to the Lord will be saved if anyone who was righteousness but turns to evil then he will be forsaken by the Lord.
How?
Be humble and fear the Lord, for God is good forever.