From who can you collect garnishment?

Hello everyone!

I'm having an urgent problem right now.

Background issue:

We live in Georgia. Recently, my father did not receive a court date notice regarding a suit, and thus the court ruled in favor of the plaintiff. We didn't know about this case until now. The plaintiff's attorney found my bank account tied to my step-mother's; he then placed a garnishment hold on both accounts and also took funds from my bank (checking) account, which I have been saving up for college.

I talked to the bank's legal team about the legality about the issue, and they said if my mother owed them money, then they have to take my money as well, because I was tied to her account.

We contacted our attorney who lives roughly an hour and a half away and he was busy, so we can't drive up until later. My father said he will first take care of the court notice problem, so that he can bring the whole case back to court. However, this still does not address the problem that I cannot use my bank account, and if it is compromised, the bank said they will send it to the credit bureau which they said will damage the credit of all the people attached to the account.

The question:

I'm assuming that taking funds from accounts that are tied together may be legal under the bank's policy. However, what is really bothering me is that it was my father involved in the case, not my mother. Did the plaintiff have the legal right to take money from my mother and me?

Thanks in advance!