Question about feeding

So I have 3 ball pythons, 2 of them are a year and 5 months old. The other is about 8 months old. They have all feed on Ft mice, and then swtiched to small-medium FT rats. They are all healthy, 2 males and a female, but they go off feed for winter. But this season I am having a hard time getting them back to eating. They used to eat when i would put the food in the cage and leave it over night. it would be gone in the morning, but now that doesnt happen. So I sit there every week and spend 20-30 min wiggeling that rat, a switched back to mice to see if a smaller prey would work. Any suggestions. They havent lost weight, but the year a 5 months old balls (one male and one female) have been off feed for about 3 months. The 8 month old took a rat 2 weeks ago but turned down one this week.
I intend on selling my snakes because I will be gone alot this summer, They are all BHB normals.. but before I sell them, I really want them to start eating again because I don't want to put it off to someone else as a problem.

I have heard of people switching to live mice totry and trigger the feeding process again, and then work back to FT... I am really bugged about feeding live, but if it is something I have to do.. then I will.

Are there any other suggestions? And any one interested in purchasing? let me know.

Thanks for reading
Michelle