If you can't delete the entry by clicking on the garbage can next to the entry, delete the entire form and re-enter.
Here's the general procedure for viewing the forms list and deleting unwanted forms, schedules, and worksheets in TurboTax Online:
Open or continue your return in TurboTax.
In the left menu, select Tax Tools and then Tools.
In the pop-up window Tool Center, choose Delete a form.
Select Delete next to the form/schedule/worksheet in the list and follow the instructions.
