Should I close my account?

Go to your bank in person, and speak wiith the branch
anager. Tell him/her what happened, and ask that the deposit be reversed. Then have them block all ACH access to your account from the company that deposited the money. Get verification of all this in writing from your bank.

You shouldn't have to mail anything back to anyone. The point here is this: You didn't ask for the money, so you aren't getting/handling the money, even to send it back.

thank you so much, will the bank charge me to reverse the deposit? do you think whoever this ssm group is will try to charge me a fee even though i never touched there money?

The bank shouldn't charge a fee to reverse a fraudulent transaction. If they do, you need another bank!

SSM may indeed try charging you. My best suggestion is to ask that question on the Payday loan board, here on DebtCC. Somebody there will have more info for you.