is ball python has period of fasting each year?

[Kaorte]

yes, I just moved to bigger cage few days ago.
may be it is the answer ...

btw .. .this evening I tried to put small baby mice into the cage and one of my female start eating it.

Moving to a different enclosure is most definitely why you experienced a refusal. There is a 7-14 day period of adjustment when you make any changes to your setup. They just need time to get used to the new environment.

From your response, it sounds like they are housed together? If so, you should probably separate them. Especially if you are throwing a bunch of mice in the cage... You should never leave live feeder unattended with a snake. If the snake doesn't want to eat, the mouse will start to eat the snake. Also, by putting mice in a cage with two snakes, they will compete for food. If you leave, you will not know who ate what