You can contact TurboTax support, they should be able to give you a download of your Desktop software if they see you purchased it from TurboTax.
TurboTax support
https://support.turbotax.intuit.com/contact/
If you purchased the Desktop software from TurboTax, there should be a download of your software in your Downloads.
Still try to contact TurboTax support, they maybe able to give you an amended software.
You can also manually amended your return.
1040x amend return
https://www.irs.gov/pub/irs-pdf/f1040x.pdf
1040x instructions
https://www.irs.gov/pub/irs-pdf/i1040x.pdf
If you need to amend a State return, you can check your State's website for their amended returns.
You can contact TurboTax support, they should be able to give you a download of your Desktop software if they see you purchased it from TurboTax.
TurboTax support
https://support.turbotax.intuit.com/contact/
If you purchased the Desktop software from TurboTax, there should be a download of your software in your Downloads.
I did not purchase the CD directly from turbo tax I purchased it from Sam's Wholesale.
Still try to contact TurboTax support, they maybe able to give you an amended software.
You can also manually amended your return.
1040x amend return
https://www.irs.gov/pub/irs-pdf/f1040x.pdf
1040x instructions
https://www.irs.gov/pub/irs-pdf/i1040x.pdf
If you need to amend a State return, you can check your State's website for their amended returns.