She’s very cute!

The problem is, now she’s peed on the sofa she thinks it’s an ok place to pee.
Normally we recommend cleaning floors etc with vinegar, but I think you might need to get a proper fabric cleaner for the sofa. Once you’ve cleaned it, I would block it off for a few weeks so hopefully she forgets she liked to pee up there!

After a few weeks, I would give her access to it again, but line it with blankets or puppy pads, so that you can easily dispose of or wash bits that she pees on. Keep a close eye on her, and as soon as you see her lift her tail, move her to the litterbox. That will help to teach her that the litterbox is for peeing. If you see her pee in the litterbox, reward her with a treat.

Peeing is also to mark, so for now, I would recommend trying the fabric technique. Grab a towel, spare shirt, or something you’d like to use to catch her scent. Feed her on the cloth, rub it on her, let her pee on it and dry, whatever to get a scent. Then lay that on the sofa on the portion she hangs around the most. This helps reduce the pee accidents since it’s claimed territory. This helped me with Wick until he was neutered.

There’s a pet spray called nature’s miracle that is pretty good at removing pee smells, it might work for your couch

The couch is a common problem for bunny pees. Thor only peed on ours once, but others make it a habit. Spaying her when she is old enough should help a lot! Young buns tend to be a little less litter trained. Wick’s idea of putting a piece of cloth that smells like her is a good one! If that doesn’t work it might be best to restrict her access to the couch until she is fixed to save your furniture