[Aegis]

This happened to my hamster pretty recently. It turns out that it was just too cold in the room. This is because your hamster is a Syrian she will want to hibernate when it gets chilly outside, I know this because all three of my hamsters have done this before. Try to fix your heating system if you can, and if not then just try adding a little extra bedding throughout the cage. If you know how to knit/crochet try making a little blanket for the hamster. She will probably love it if you do this because it is warm and will smell like you, which should bring her comfort. I hope your hamster warms up again, have a good day!
-Aegis