After you have entered the W-2G form, on the page labelled Here's your W-2G info, click on the trash can icon next to the W-2G you want to delete.

I need to remove gambling winnings that are not on a W-2G.  Thanks anyway

You will find gambling winnings in the "Income and Expense" section of Turbotax, and then "Less Common Income". Just go back into the "Gambling Winnings" section to remove the entry you made there. 

I removed where I entered gambling winnings and didn’t mean to. It’s still showing on my return where it was entered but the document is deleted 

Please follow the steps here, to ensure the form is truly deleted from within Turbo Tax. 

Then please preview your 1040, to check and see if the income is correct. Then you can add the form back into Turbo Tax. 

Once you have added it back, please preview the 1040 once more, to ensure your income has not doubled. 

If you need additional assistance, please click here to contact customer support.