If you are in forms mode, search for Investment and click on *INVEST. You will be brought to the form "Statement of Investment Income". You will need to delete the appropriate entries on this form.
If you are in Easy Step, under your Profile => Personal tax profile, make sure you checkmark "I have incurred expenses to earn investment income...". (See picture) Click Continue.
Then under the Income & Expenses, you should see "Investment Expenses". Go through that portion of the Easy Step and delete the relevant entries.