Please clarify @rbr6596 by telling us what state you are filing. State forms are all laid out differently so it's possible the information may be on another part of the form, such as the signature line.
Form MO-1040 includes a box to show one of the filers is deceased. It's right above the address line.
Missouri requires additional information as well:
In order to claim a refund for a decedent, the following documents are required:
Send all required documentation to Missouri Department of Revenue, P.O. Box 2200, Jefferson City, Missouri 65105-2200.
Please see this Turbo Tax FAQ on when to amend.
https://ttlc.intuit.com/community/amending/help/do-i-need-to-amend/00/27607