The IMC was not locking. I did the following items to let it lock:

1. The FSS trans threshold was decreased from 0.8 to 0.7 because it kept dropping its lock.
2. I lowered the limitter for MC2_M3_LOCK_LIMIT to 4e5 from 6.4e6. It seems this was intentionally increased to the high value yesterday. Though I am not sure how effective this low limitter value is.
3. I ran als/h1/scripts/COMM_down.

Now it locks.