Mom died, last social security check was returned, then paid to me. I have ssa-1099, entered box 5 into turbotax, it shows that 100% is taxable rather than the 85%. Why?

Box 5 shows on income summary on TurboTax at the full amount. Soc Security worksheet that i did manually shows that only 85% should be reported as income. Will TurboTax adjust this downward, because it hasn't yet and is calculating refund based on 100%.