Moh#1

I have city with 1,100,000 people (It use to be 1,500,000 but I removed all buildings that have went brown and my population droped to 500,000 then up to 1,000,000 and I lost all my S sims which was kind of a good thing) now I want to get SSS but 800,000 of my sims are SS and only 100,000 are SSS. I tried everything but they won't come and I don't want to use cheat codes or mods. got any idea?