False pregnancy, obsessive nesting

My bun is 3-4 yrs old, not spayed. I've had her less than a year. This is my 1st bun. I've read about false pregnancies and noticed she was nesting a couple days ago. Was worst yesterday. She's in an indoor hutch with 2 levels and 2 litter boxes. She is using 2nd level, smaller litter box, for the nest. She is moving EVERYTHING she can carry to it. I thought I should leave it alone and let her do what she needs to with it but I don't want to encourage this behavior. When I let her out in the xpen she tries to carry everything in it to her hutch, tissue paper, sticks, hay mat. She's also a bit nippy. Obsessively working to get this done. She is so busy it doesn't look like she's eating much hay and for the 1st time, didn't finish her pellets from last night! I would like to clean her litter box/nest but not sure if that would help or make it worse for her. Is there anything else to I can do to help end this. I do intend to have her spayed but until then.... thanks for any advice!

You can't really stop the impulse they are having. Only way is to get her spayed.

You should also be aware that an obsessive nesting impulse can be an indication of uterine abnormalities/cancer developing. I had an older doe and before I could get her spayed she started having obsessive nest building behavior that kept reoccurring and pretty much didn't stop. She also didn't eat well because of this ongoing impulse. I suspected it could be a uterine problem/cancer developing so I immediately got her spayed. And she was completely fine after that. So I would suggest immediately scheduling a spay surgery with an experienced rabbit vet.
https://rabbit.org/vet-listings/