Hello,
As most know, the SetAge cheat stopped working a few updates ago. I've found the replacement, although it behaves a bit differently (in a good way)
The old cheat only allowed you to set age to an adult. This one lets you age any sim into their next age phase.
Age Up Active Sim:
sims.age_up
Age Up by Sim ID:
sims.age_up <simID>
I've updated the cheat on my wiki as well.
If you need to set your sim to a previous age, I've also updated my SetAge cheat mod which will let you do so:
TwistedMexi's Cheat Resource - Custom Cheats