Yes, you need to amend your return.
The amount in Box 1a of Form 2439 is the total undistributed long-term capital gain from your regulated investment company (RIC) or real estate investment trust (REIT). It needs to be reported as a long-term capital gain on line 11, column (h) of Schedule D.
If you used TurboTax Online and need to amend your return, log in to your account and select Amend a return that was filed and accepted.
If you used the CD/download product, sign back into your return and select Amend a filed return.
