I accidentally added a form to my tax return which is giving me red diagnostics. How do I clear out the diagnostics?

You can go to 'Review Diagnostics' and click on the red error. On the right-side of the pop-up window (under Explore), click on the link that will open up the form. Take note of the name of the form. Then, go to 'Form Manager' and search for the form. After having opened it, click on the 'Remove Form: (Name of form)'. This will clear out the diagnostics.