Having forced his realm to improve twice in succession, Gu Ding suffered the backlash of the realm, and making a move now would do him no good at all.
It was better to let Su Chen go for now, and wait until he recovered from the realm backlash before locking onto Su Chen.
Unless Su Chen chose to abandon the Hall of Reincarnation, that was the only way he would shake off the lock.
Chapter 1654