If she's 1,200G, she can go a while without eating. 70 days doesn't sound like a lot to me, unless you have other health concerns and/or she's losing weight rapidly. My female BP, Shayna, fasts for 5-6 months every winter like clockwork and used to eat sporadically the rest of the year as well. I don't even think about worrying unless she loses more than 10-15% of her body weight. She is about 2KG/2,000G for reference.
The way I got her to eat more consistently is to feed small rats (60-90g) and stop feeding mediums (100-150G). She happily takes frozen, when she wants to eat, and barely ever skips a meal unless in fast or in shed. When I fed mediums, she would often skip meals and have periodic fasts. Now, it's only winter fasting and I feed the small F/T rats every two weeks (I offer 1X a month +/- if she is in her winter fast).
I agree with leaving her alone. I do not encourage feeding live or ASF Rats. The former might get her off F/T for a bit and the latter could get her hooked on ASF Rats. Unless you have a steady supply of ASF's for the life of your BP - 20-30 years or more if cared for properly, I recommend sticking with "normal/domestic" rats.
Again, I really wouldn't be worrying at all at this point unless she's suddenly lost a ton of weight and/or is showing other symptoms that are worrisome.
Take a deep breathe and offer a small rat (F/T if that's what she was eating) every 4 weeks until she starts eating again. Offering too much can stress her out and make it more likely she doesn't eat and perpetuate the problem.
Good luck and keep us posted.