Try it again, it might have just been a fluke of the RNG. Also check your team again just to be sure--I always run HK as my leader, but the game seems to default to IG-88. So if I'm not careful I go in with the wrong team.
I haven't improved my team much since last time it was run and I was able to finish T1 and T2 no problem, and only needed a second try for T3.
I'm not trying to sound like, "WELL I CAN DO IT SO ITS FINE DO BETTER NUUUUB," sorry if it comes across that way. But I've had flukey runs of mundane things in the past, and trying again usually works because bad luck doesn't last forever.
It's also possible that you overperformed T1 and T2 last time around--flukey good luck, as it were--and now you're falling back to earth. The important question, though, is: Did you finish? Because if you did, wel........