After I paid Turbo Tax, they were unable to file my taxes because "they had already been filed" How do I get a Refund from Turbo Tax for what I paid them?

Did you file them using another tax preparation service? If you did, why did you prepare a return and pay using TurboTax?

If you did not already file a return, perhaps you used the non filer portal to register for the stimulus payment. Using that portal efiles a tax return for you but it has $0 income so all it does is prevent you from efiling your "real" return. If that is what you did, you still need to file your "real" tax return. Here is what to do about it: https://ttlc.intuit.com/community/tax-topics/help/stimulus-how-to-file-your-return-after-getting-reject-r0000-902-01/01/1602609

If you want to try to request a refund, you must contact TurboTax directly for this. 

https://ttlc.intuit.com/community/using-turbotax/help/what-is-the-turbotax-phone-number/00/25632

TurboTax does not give refunds for tax returns that can't be efiled. The fees are for the use of the tax preparation software to prepare your return. The fee is the same whether you efile or print and mail your return.