you may have incorrectly written off that loss. you say it was not a Ponzi scheme. if the loss occurred prior
to 2018 it was probably a deductible casualty loss reportable on form 4864 - an ordinary loss reportable on schedule A not a schedule D capital loss. if it occurred after 2018, due to changes in the tax laws, it was not deductible at all because it was not a Ponzi scheme. I think you need to consult a pro to recommend a course of action
