It depends. If you have been reporting this from Schedule K-1 provided by the company, you should indicate in the K- interview that you received a final K-1 (the partnership/S-Corp ended) and that you "disposed" of your interest in the company but not in a sale.
If you have not reported the activity from this investment before, you would enter this as an Investment Sale under Investment Income >> Stocks, Crypto, etc. In this case, you would need to know your basis (purchase cost adjusted for any income/loss) and report zero sales proceeds.
In both cases, TurboTax will calculate the loss from the investment and report that on the appropriate forms.