Okay, I did everything for her to live: I met her 3 times, warned her about Kai Leng, (which happens automatically when you meet up with her via video conference in the Spectre Office), and also I gave her the Alliance resources.
I didn't romance her in 2 or 3 because my Shepard is female and, I'm sure we're friends. In my ME2 save, she was loyal and survived the Suicide mission.
I chose the paragon option when I met Henry Lawson. He let Oriana go but Miranda still dies. I also tried the exact same thing but with choosing the Renegade option at the end, to no avail.
So I went far back to my save where FemShep just finish the mission about the Catalyst and Kai Leng stole that Prothean Tech. I thought how quickly you do the Sanctuary mission affected the outcome of Miranda's life - either she dies or lives, but that didn't do anything.
So here, I searched up all the possible ways and the topics on Miranda surviving. I even went to Youtube for that and even searched for cheats but really, nothing came up. Is there something I'm missing?