Net Investment Income Tax (NIIT)

I have dividend income from a LLC partnership in which I materially participate. My understanding is that because I materially participate in the LLC I am NOT subject to the 3.8% Net Investment Income Tax (NIIT) on this dividend income (i.e., it is NOT considered passive activity because I materially participate). However, TurboTax Deluxe 2021 appears to be including the income and calculating my NIIT accordingly. I can see where the electronic K-1 form in TurboTax has the "material participant" box checked, but it only appears to apply to ordinary business income ($0, in my case), not the dividend income. How do I get TurboTax to recognize the dividend income is NOT taxable because I materially participate in the LLC that issued my K-1?