Turbotax can't help you. You have to check your records to see if the balance due was paid. Check the return for the balance due. if paid, get a copy of the payment (front and back and account statement) and send those documents with the notice to the address indicated with a letter stating the balance was paid - documents enclosed. sign and date the letter. if you have questions about which payment the IRS is referring to, you'll need to check your account transcript
https://www.irs.gov/individuals/get-transcript
