l Tried to activated license by CLI, and it worked
l All APs became normal again
l But with further checking, we found that was trial one
l And we analyzed more, we found that the license was activated by the ESN of MPU not the chassis.
l Issue is solved after ESNchange for the permanent license
The right license was activated but was wrong ESN.
As a sequenmce, Trial license was activated(due to wrong ESN), so when it was expired, only 16 AP became normal.
l Issue is solved after ESNchange for the permanent license. then deactivate the wrong one at AC, and the final step was activating the new license with the right ESN