The notice you received from the IRS should indicate what they changed on your filed tax return so that the taxable amount of your Social Security benefits increased. If you have questions concerning the IRS notice then call the number provided with the notice and speak with an IRS agent.
You can also get assistance in understanding the IRS notice you received from a TurboTax agent at the Audit Support Center. Use this website to access the Audit Support Center - https://support.turbotax.intuit.com/irs-notice/audit-support/
The notice you received from the IRS should indicate what they changed on your filed tax return so that the taxable amount of your Social Security benefits increased. If you have questions concerning the IRS notice then call the number provided with the notice and speak with an IRS agent.
You can also get assistance in understanding the IRS notice you received from a TurboTax agent at the Audit Support Center. Use this website to access the Audit Support Center - https://support.turbotax.intuit.com/irs-notice/audit-support/
They don't just change your SS taxable amount. What happened was they increased some other income on your return which made more of the SS taxable. Usually they change the taxable amount of any 401k or IRA distributions or conversions you got. Did you get any 1099R forms? Check 1040 lines 15b and 16b. Or you completely left out some other income you got.