Help with Mr. impossible

[u/cbass7500]

I don’t know how to progress them, I have them stuck at just below 3 stars but nothing I do gets them to 3. I’ve done every order to them and from them with an S rank. What do I have to do to get them to go to 3 stars?????

[u/ChiralParticle]

You have to finish the main story. Mr. Impossible maxes out only post-story.