Your best option is to start over and re-import the prior year return. This will preserve all the information for the deleted partner. In TurboTax Business, simply start a new return for this year.
Your other option is to add back the deleted partner with a change in ownership. Use January 1 as the change date and set up all the ownership & capital information as it was before. Check to be sure your balance sheet is still in balance and review the Sch K-1 Wks in case you missed any input.