the tax consequences depend on facts we don't have. Did you manually not deduct the losses shown on the k-1 for all those years or did you let Turbotax determine the deductibility based on being an LP without active participation? Those losses reduced your outside tax basis regardless of deductibility. Thus if your tax basis went negative with the distribution that's a taxable LTCG to the extent of a negative tax basis. in that case your CPA was correct and your tax basis at the start of 2022 would be zero. The 2022 tax basis would go up by any income but not down by any loss since your tax basis is already zero from the end of 2021.
in 2023 your tax basis would go up by any 2023 income any 2022 loss would now be allowed to the extent of income but evidently you got no cash in 2023. Thus you have tax basis for which you got nothing so you take a capital loss on termination of the partnership. so in the end you don't pay tax on the K-1 report gain for 2023
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now let's assume the distribution in 2021 did not create a negative tax basis (yes you'll need to amend 2021). then any 2022 loss would reduce any remaining tax basis and income would increase it. 2023 income would also increase your tax basis. Thus you would have a positive tax basis for which you received nothing in the 2023 liquidation. thus again you have a capital loss on termination. this gets reported by checking the proper boxes for the k-1 as you go through then Turbotax will ask about termination information. the loss would flow to schedule D. so in the end you don't get double taxed on the 2021 distribution.
