Plugin using tax in free shipping calculation

I have free shipping set up for orders over $100. When I add a product to the cart for $99 (https://concordwindow.wpengine.com/product/comfortech-35/?attribute_pa_window-type=patio-door&attribute_pa_product-type=1-window-kit) it does not trigger free shipping. However, once I put in my address and it calculates taxes ($99 + $6.19 tax = $105.19 total), it’s offering free shipping. How do I keep the plugin from using tax in the shipping? We are using TaxJar to calculate shipping.

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