I ,too, am having the same issue. I believe you may be referring to the Tencent special dividend for the distribution of JD.com shares.
I have read in other messages in the TT Community to state 0 (zero) as the cost basis. Further reading indicates that this distribution was a "return of capital (ROC)", thus, not a sale that would require a cost basis.
See: Solved: Re: UNDETERMINED TERM TRANSACTIONS FOR NONCOVERED TAX LOTS on ADR Dividends (intuit.com)
I am also getting an error in TT asking me to enter the "Date Acquired" - but since this is a ROC and not a sale - I don't see why that info is required. It allowed me to enter "N/A" in the Capital Gain worksheet but "N/A" is not acceptable in the Capital Asset worksheet. Are you having this problem also?
Hope some of this info helped.
