I am trying to override sales tax on my products. I have a license to tax in Pennsylvania, but when I try to override for other states in the drop down menu, it only shows Pennsylvania. I am new to Shopify. I do not know how to collect taxes from my customers outside of my states when I sell online. I have been paying the out of state tax all year because I have not known all this time that this is what I should have been doing. Can some one please help! Thank you.