Taxes for warranty extensions vary in different states

Hello,

one of the products we sell in our store is an extended warranty for refrigerators which are also offered in the store. Now we have the problem that in some states taxes are levied on the sale of extended warranties and in other states they are not (e.g. California). Unfortunately, there is no suitable category for this service in the product management, so that when calculating with Shopify Taxes it can be differentiated whether the order item is a regular item or an extended warranty.

How do you handle the taxation of additional guarantees in Shopify to meet state taxation requirements? We have to check for each order with an extended warranty whether the tax charged for it is correct or not.

Many thanks in advance.