[cypher]

If she's grooming rather than scratching it may be that you're cleaning too much & she's constantly scent marking to get her scent around the cage, you have very little substrate in your cage really which makes it hard to just spot clean & not take out too much substrate.
How often do you clean the cage?
All you really need to do is spot clean pee when you find it then just do partial cleans as & when it really needs it, maybe do one area of the cage every few weeks leaving the nest & hoard alone as much as possible.
If you give a good deep layer of substrate (at least 15cm) it makes it easier to just do partial cleans & you'll find you need to clean less, it would also mean she could dig & burrow & make a proper nest.
If she's scratching a lot then it is possible there's a problem like mites but you would usually see some fur loss around the head area if that were the case.