My rabbits fur is falling out and I'm pissed

Lexi • 19 years old/ Insta: lexihedlof

So recently I let this bunny Lady come take my rabbit to go get her spayed. Her fur was perfectly fine and normal before she left. I noticed some parts of her fur looked darker then the rest when she came back but I figured the vet just brushed her. Well no. I was wrong.

Thumper has a huge patch of fur missing. I just realized this today and she's been home for almost 2 weeks. Her fur isn't growing back, it's just falling off and her along under the fur is pealing off as well. I messaged the lady and told her. Hopefully she responds but I'm pissed.

Thumper is 4 years old, but most 4 year old rabbits don't have fur falling off them. Even when I was petting her a little section of fur fell out.

Could this be the rabbit Ladys fault or the vets?