Did you use the same TurboTax Online account to prepare both returns? Each return prepared using the online platform must have its own separate account. If you DID use TTOnline, maybe you created an entirely different account for the second return (as you should) and used a different password.
If you used only one TurboTax online account to prepare and file 2 different returns, the second return has "overwritten" the first one. All you'll be able to find is the final return you prepared using the same account.