That is the main issue that you would have on appeal, since you will, unfortunately, definitely have to repay the money that you received in overpayment.
You can file an appeal regarding the penalty that was imposed on you for fraudulently receiving an overpayment in benefits. It was likely imposed on you since you did not report the income that you received and stated that you were not working.
It will definitely be difficult to win on appeal, since every claim form that you fill out has a signature where you state that you verify that everything on the form is true, including that you were not employed and not receiving income from any sources.
Unless you can prove to the EDD that you really had no knowledge that you had to report the income from your job, I'm afraid that you'll probably wind up being liable for the penalty as well. You may be able to do so, but, from my experience, it's pretty hard to do with an administrative judge.
You can arrange a payment plan with the EDD, however, so you won't have to be liable for the entire overpayment and penalties immediately.
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